Surgical apparatus and method for performing transabdominal cardiac surgery

ABSTRACT

An intervention is performed on a target anatomic structure of a patient body by first altering the configuration of the diaphragm through displacement or puncturing of the latter, in order to create a passageway leading into the thoracic cavity. An implement is introduced into the thoracic cavity through the passageway. The implement is then used while extending through the passageway to alter a biological tissue of the target structure or manipulate the latter. Optionally, a separating component having a peripheral wall encompassing a component channel is introduced into the passageway for receiving the implement and separating the latter from the non-target anatomic structure.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation application of U.S. patentapplication Ser. No. 09/488,557, now U.S. Pat. No. 6,478,028, filed onJan. 21, 2000.

FIELD OF THE INVENTION

The present invention relates generally to a surgical apparatus andmethod for performing less-invasive surgical procedures, and morespecifically, to a surgical apparatus and method for performing asurgical procedure on the beating heart, such as stabilizing a portionof a beating heart during a coronary artery revascularization, whereinsaid surgical procedure is performed through a percutaneoustransabdominal approach.

BACKGROUND OF THE INVENTION

Cardiac surgery, and more specifically traditional coronary arterybypass graft (CABG) surgery, has been performed since the 1970's on aregular basis with the advent of the cardio-pulmonary machine. Intraditional CABG, the patient's heart is exposed by cutting through thepatient's sternum and retracting the two halves of the ribcage. Theheart is subsequently stopped while the blood continues to be pumped andoxygenated outside the body through extracorporeal circulation (ECC).The development of the cardio-pulmonary machine for ECC enables surgicalinterventions to take place on an arrested heart. This allows thesurgeon to manipulate and operate on a perfectly still heart. As such,the arrested heart may be positioned to expose and provide the bestaccess to the target artery requiring a bypass grafting.

However, there are two main invasive aspects associated to traditionalCABG—the sternotomy incision and the ECC. Even with the constanttechnological improvements achieved during the last twenty-five years,the advantages offered with ECC have been at times offset by themorbidity (complications) and mortality related to the ECC itself. ECChas been documented to produce some well-known complications. Adverseeffects associated with its use continue to be discovered and as such,ECC represents one of the most invasive clinical aspect associated withtraditional CABG surgery. The inflammatory response, as well as thesystemic microembolisms generated by ECC, induce to some extent adysfunctional state of the brain, lungs, and kidneys, which tends toincrease with the aging of the patient. Furthermore, evidence suggeststhat when ECC can be avoided, the left ventricular function (pumpingefficiency) of the heart is better preserved, thereby also reducing therisks of postoperative complications and the need for ventricular assistdevices to wean the arrested heart back to normal function. In additionto being one of the most invasive aspects of traditional CABG, ECC isalso responsible for a large percentage of the initial procedure cost oftraditional CABG. If ECC-related complications develop, ECC is alsoresponsible for the post-operative costs incurred to treat thesecomplications.

A median sternotomy, although less clinically-invasive than ECC, has theperception of being more invasive due to the surgical scaring thatresults from the surgery. A full median sternotomy may result in atemporary disturbance in the respiratory mechanism, an increased risk ofoperative shock or dehiscence, and re-operation surgery from bleedingcomplications. Moreover, prolonged exposure to air of the exposedmediastinum may lead to hypothermia, infection or compromise of theneuro-endocrine response. Patients with severe chronic obstructivepulmonary disease (COPD), severe emphysema or severe pulmonaryinsufficiency are therefore at a higher risk of developing complicationswhen exposed to a sternotomy incision.

Port access surgery, developed largely by Heartport Inc. of RedwoodCity, Calif., consists of replacing the full median sternotomy by aseries of intercostal port incisions in the patient's chest, throughwhich coronary artery revascularization is performed. However, the mostinvasive aspect, ECC, is retained in this type of surgery. The patient'sheart is arrested by occluding the patient's aorta preferably betweenthe coronary arteries and the brachiocephalic artery with an expandableballoon on the distal end of an endovascular catheter which may beintroduced via a femoral artery. Cardioplegic fluid is then delivered tothe patient's myocardium through a lumen in the same catheter or througha separate catheter positioned in the coronary sinus. A series ofcannulae and catheters are usually employed to divert the patient'sblood flow to the cardiopulmonary machine and to return the oxygenatedblood to the circulatory system while the aorta remains occluded toavoid backflow into the heart chambers and surgical field. The portaccess approach most often also requires lung deflation in order toimprove the access to remote territories of the heart, such as theposterior coronary territory. Unlike traditional CABG, the longitudinalaxis and apex of the heart cannot be “verticalized” with respect to thesurgical table and retracted chest cavity tending to facilitate accessto the posterior territory. Performing port access surgery remotelythrough a number of small ports tends to be difficult, at times leadingto unwanted tissue dissection that requires the conversion to a fullsternotomy in order to complete the surgical procedure.

In recent years, the drive for less-invasive and cost-effective surgicalapproaches and apparatus has placed emphasis on cardiac surgery as well.However, unlike other organ surgeries, gall bladder for instance, thebeating motion of the heart tends to complicate the surgicalintervention.

In minimally invasive direct coronary artery bypass graft surgery(MIDCAB), ECC is avoided and coronary artery revascularization isperformed directly on the beating heart with the help of a mechanicalcoronary artery stabilizer, through a mini-sternotomy ormini-thoracotomy incision. This surgical approach allows access to onlyone or two of the anterior arteries of the heart, most commonly the leftanterior descending artery (LAD). Demographically, only 5-15% of thecardiac surgery population is afflicted with single vessel disease; themajority of cardiac patients (70%) suffer from triple vessel disease,whereby at least one artery on each of the anterior, inferior andposterior territories of the heart requires a bypass graft. As a result,this approach has also been referred to as “limited access bypasssurgery”. Moreover, the MIDCAB thoracotomy incision to access thebeating heart has been discovered to be more painful and less toleratedby patients than originally anticipated, especially in younger patients.

More recently, the beating heart approach through a sternotomy incisionhas been adopted tending to facilitate positioning of the beating heartwithin the retracted chest cavity and tending to facilitate grafting ofthe difficult to access posterior arteries. Mechanical coronary arterystabilizers have been developed to immobilize a portion of the beatingheart surface proximate to the target artery during the distalanastomosis phase of the surgery. A median sternotomy is desirable sinceit tends to allow the apex of the beating heart to clear the retractedribcage as the heart's longitudinal axis is “verticalized” in order toexpose the posterior coronary territory. In some patients,verticalization of a beating heart is not well tolerated and may lead tohemodynamic instability during the surgical procedure. At times, thisunnatural “verticalized” orientation of the beating heart may beattained with some degree of atrial or ventricular distortion, and evensome degree of valvular dysfunction and regurgitation. Moreover,although the beating heart approach achieves the elimination of thecardiopulmonary machine, the sternotomy incision with its associatedcomplications is retained in this approach.

Percutaneous transluminal angioplasty (PCTA) or Coronary Stenting areintraluminal surgical procedures which achieve coronary arteryrevascularization through the enlarging of restricted vessels by balloonangioplasty (PTCA) and in some cases also supplemented by thescaffolding effect of the tubular mesh stent. Sternotomy incisions andECC are avoided since the entire procedure takes place through thepatient's artery. However, the high incidence of restenosis associatedwith PTCA, and its generally low endorsement in the treatment of triplevessel disease does not make this procedure suitable to the majority ofcardiac surgery patients that require coronary artery revascularization.Other emerging technologies, such as Transmyocardial Revascularization(TMR) or Percutaneous Myocardial Revascularization (PMR) are reservedfor surgically non-reconstructible coronary artery disease.

It would therefore be advantageous to have a surgical apparatus andassociated surgical approach which maintains, as much as possible, thenormal anatomic position and orientation of the heart during a surgicalintervention. One aspect of the present invention aims to provide accessto the posterior coronary territory of a beating heart during CABGsurgery, without the need for a sternotomy incision, and while thelongitudinal axis of the beating heart is maintained as much as possiblein its natural, substantially-horizontal anatomic orientation. Thecombination of the beating heart approach with a surgical approachattempting to access all coronary territories without the need foreither a sternotomy or thoracotomy incision would therefore offerdistinct advantages in reducing the risk of complications and minimizingthe surgical scaring normally associated with current CABG surgeries.

A percutaneous incision in the abdominal region below the patient'sribcage, and the subsequent creation of a trans-abdominal,trans-diaphragmatic tunnel may provide a suitable surgical approach toattain the patient's thoracic cavity. The patient's heart and internalcardiac tissue may then be accessed by a variety of surgical instrumentsextending through an access cannula placed in said trans-abdominaltunnel and extending beyond an anatomic barrier, such as the patient'sdiaphragm. A number of surgical manipulations and interventions may thenbe performed by selected surgical instruments on the target tissue suchas the patient's heart or other internal cardiac tissue. Internalcardiac tissue includes but is not limited to the pericardium,epicardium, myocardium, endocardium, apex of the heart, ascending anddescending aorta, vena cava, coronary arteries and veins, internalthoracic arteries, pleurae, endothoracic fascia, and other like anatomictissue.

One aspect of the present invention describes a surgical apparatus thatallows the manipulation and positioning of a beating heart within thepatient's thoracic cavity, along with the deployment within thepatient's thoracic cavity of coronary stabilizers that serve toimmobilize a portion of said beating heart proximate to a targetcoronary artery, through a trans-abdominal tunnel. This aims to allow atleast some surgical interventions associated with coronary arteryrevascularization to be performed without the invasiveness of ECC andwithout having to perform bone-cutting or bone splitting incisions suchas sternotomy, intercostal thoracotomy with spreading of adjacent ribs,or other like surgical incisions. This tends to provide a closed chestsurgical approach to perform cardiac interventions. The arteriotomy anddistal coronary anastomosis, although may be performed through a numberof intercostal ports not requiring the bone splitting or bone spreadingincisions, are also preferably performed through the trans-abdominal,trans-diaphragmatic tunnel. In the present invention, the term “closedchest” will refer to surgical procedures which keep the patient'sthoracic structure intact.

It is therefore an object of the present invention to provide a surgicalapparatus and method that enable coronary artery revascularization onthe beating heart without the need for ECC, and without having to spreadapart the patient's thoracic bone structure through a sternotomy,thoracotomy or other like incision.

It is a another object of the present invention to provide a surgicalapparatus and method that enable cardiac surgical interventions, notrestricted to only beating heart CABG, to be performed without having tospread apart the patient's thoracic bone structure through a sternotomy,thoracotomy or other like incision.

Some of the aspects of the present invention may also apply to othertypes of surgery, such as laparoscopic, endoscopic, or thoracoscopicsurgery, whereby surgery is performed on target tissue contained withinan internal body cavity that is accessed by surgical instrument disposedthrough an access cannula. Here the manipulation of surgical instrumentsduring a surgical intervention performed through an access cannula maybe better effectuated if said instruments are engaged with an internaljoint within said cannula. Also it may be desirable in such surgicalprocedures to be able to secure said joint and maintain engagedinstrument in a desired fixed position and orientation relative to theaccess cannula, at least for a part of the surgical procedure. Thesurgical procedure may also be further improved if the access cannula isalso engaged with a movable joint connected to a stable surgicalplatform, whereby said joint may also be secured by a tightening meansto maintain access cannula in a desired fixed position and orientationrelative to patient and surgical table. The access cannula may alsoserve to introduce into the internal cavity surgical aids which may notengage target tissue during a surgical intervention, but help facilitatea surgery through their installation. For example, a camera lens or afiber-optic bundle to provide light.

It is a further object of the present invention to provide a surgicalapparatus and method that tends to facilitate endoscopic surgery, morespecifically endoscopic surgery where a surgical procedure is to beperformed within an internal body cavity beyond an anatomic barrier,through the use of surgical instruments introduced therein through anaccess cannula.

These and other objects of the present invention will become apparentfrom the description of the present invention and its preferredembodiments which follows.

SUMMARY OF THE INVENTION

The present invention provides an access cannula with a substantiallyopen proximal end and a substantially open distal end, and at least onesubstantially hollow passageway extending from said open proximal end tosaid open distal end. The outer surface of the access cannula ispreferably engaged with at least one anatomic barrier. Target tissue islocated in an internal body cavity or region downstream of an anatomicbarrier and generally beyond the distal end of access cannula. Theaccess cannula provides access, beyond at least one anatomic barrier, toa variety of surgical instruments which are able to extend beyond thedistal end of access cannula. Some instruments will engage target tissueduring at least a part of the surgical procedure they are intended for.

Instruments are preferably engaged with access cannula through aninternal joint which may provide a number of motion degrees of freedomto said instrument when they are engaged with access cannula. Surgicalinstruments may be demountably engaged with access cannula, orpermanently engaged with respect to access cannula, or may even beengaged with access cannula via a cartridge in which they are disposed.Surgical instruments may be secured in a desired position andorientation relative to access cannula and relative to a target tissuethrough a tightening element.

Proximal end of surgical instruments extend beyond proximal open end ofaccess cannula, thereby allowing the surgeon to manipulate said proximalends. Proximal manipulations on a proximal end of a surgical instrument,usually applied extracorporeally by the surgeon, are linked through anengagement with an internal joint to distal movements of a distal end ofsaid instrument within an internal body cavity.

The hollow passageway through an access cannula may be partitioned tocreate additional segregated passageways. Alternatively, substantiallylongitudinal access lumens extending generally from proximal end to thedistal end may also be provided for engagement with surgical aids. Sealmembers may be provided across hollow passageways in order to maintainan internal body cavity, situated downstream of an anatomic barrier, ata different ambient condition than an extracorporeal region.

Vision ports such as stereoscopic camera lenses, that transmit images tothe surgeon so that closed chest interventions may be remotelyperformed, are deployed within an internal body cavity either through atransabdominal tunnel or through additional intercostal port incisionsin the patient's chest. Carbon dioxide is used to displace abdominalorgans during the deployment of surgical instruments used to create atransabdominal tunnel. Passages in the access cannula are also providedfor the channeling of carbon dioxide gas into the pleural space.

Access cannula may be manipulated and held by hand, but it is preferableto have it engaged with a stable support such as a surgical table. Asurgical arm enables access cannula to be reoriented and repositionedrelative to a surgical table and also the patient's body. Once a desiredposition is achieved, access cannula is secured into position.

In performing a beating heart surgery, a variety of different surgicalinstruments may be engaged with access cannula, some are deployed alonewhile others may be deployed in combination. In one aspect of theinvention aimed to perform coronary artery revascularization on abeating heart, a surgical apparatus is provided comprising an accesscannula which is inserted through the diaphragm of the patient such thatthe distal end of cannula attains the pleural space. A heartmanipulator, engaged with an internal joint inside the hollow passagewayof access cannula engages the surface of the beating heart, preferablythe apex, when said distal end of heart manipulator extends beyond thedistal end of access cannula. Once a desired orientation and position ofthe beating heart is achieved, its position is secured relative toaccess cannula by an internal joint. A coronary stabilizer, also engagedwith an internal joint inside the hollow passageway of the accesscannula is then subsequently deployed. Coronary stabilizer is placed ona portion of the surface of a beating heart proximal to a target arteryin need of anastomosis. The invention allows the surgeon to position acontact face on the surface of the beating heart and apply a gradualmechanical force until the portion of myocardium around the targetartery is stabilized and rendered substantially motionless relative tocannula, while the rest of the heart continues to beat. The coronarystabilizer is subsequently secured. In approaching other vessels of theheart, as in multi-vessel CABG surgery, the access cannula may berotated about its centerline relative to the heart and body in order tooptimize the position of the heart manipulator and coronary stabilizerrelative to the target heart tissue. The surgical apparatus aims toprovide a way of accessing all territories of the heart by thedeployment of an access cannula, and subsequent deployment of a heartmanipulator and a coronary stabilizer relative to access cannula and toeach other.

Another aspect of the invention describes a surgical method in which thesurgical apparatus may be used to perform coronary arteryrevascularization on the beating heart through an access cannulainserted through a transabdominal approach. This surgical method avoidsthe ECC and is less invasive for the patient. This surgical method alsoavoids the need for cutting the patient's ribcage, or spreading apartribcage or removing part of patient's rib in order to access thepatient's heart such as is the case with conventional CABG surgery orbeating heart surgery performed through a sternotomy, thoracotomy, orother like incisions.

BRIEF DESCRIPTION OF THE DRAWINGS

For better understanding of the present invention and to show moreclearly how it may be carried into effect, reference will now be made byway of illustration and not of limitation to the accompanying drawings,which show an apparatus according to the preferred embodiments of thepresent invention, and in which:

FIG. 1 is a perspective view of a first embodiment according to thepresent invention illustrating a surgical apparatus for performingbeating heart CABG through a transabdominal tunnel;

FIG. 2 is a perspective partial cutaway view of the patient illustratingthe insertion of a laparoscopic cannula into the abdominal incision toaccess the pleural space, according to the present invention;

FIGS. 3A and 3B are perspective views of the thoracic cavityillustrating the deployment of the access cannula of FIG. 1;

FIG. 4 is a lateral section view of a diaphragm tissue retractor in aclosed position engaged with the diaphragm according to an aspect of thepresent invention;

FIGS. 5A and 5B are sectional views illustrating a method of engagementof the access cannula of FIG. 1 with an anatomic barrier;

FIG. 6 is a partial lateral section view illustrating the mechanical armof FIG. 1;

FIG. 7 is a lateral cross section view illustrating the heartmanipulator, coronary stabilizer, and access cannula of FIG. 1 engagedwith the beating heart and the diaphragm;

FIGS. 8A and 8B are end views illustrating several variants of accesscannulae and variants of the internal joints according to the presentinvention;

FIG. 9 is a lateral cross section view through the heart manipulator ofFIG. 1;

FIG. 10 is a perspective view of the coronary stabilizer of FIG. 1illustrating the motion degrees of freedom;

FIGS. 11A and 11B illustrate the cooperation of the access cannula, theheart manipulator and the coronary stabilizer of FIG. 1 in gainingaccess to the different coronary territories;

FIG. 12 is a lateral section view of the thorax illustrating thedeployment of a pericardium retraction device according to an aspect ofthe present invention;

FIG. 13 is a lateral section view illustrating a variant of thediaphragm engagement means of the access cannula of FIG. 1;

FIGS. 14A to 14C illustrate variants of internal joints and seal meansin the nature of a radial bellows according to an aspect of the presentinvention;

FIGS. 15A to 15D illustrate the positional relationship between theheart manipulator and the access cannula of FIG. 1;

FIGS. 16A and 16B illustrate an access cannula with a variant seal meansin the nature of compliant leaflets according to an aspect of thepresent invention;

FIGS. 17A to 17D illustrate the range of motion available to a variantof a heart manipulator engaged with an access cannula according to anaspect of the present invention;

FIGS. 18A and 18B illustrate variants of a heart contacting member ofthe heart manipulator of FIG. 1;

FIG. 19 is a schematic representation of the range of motion afforded toa surgical instrument within an access cannula according to the presentinvention;

FIG. 20 is a perspective view of a second embodiment according to thepresent invention illustrating a surgical apparatus comprised of anaccess cannula, a heart manipulator, a coronary stabilizer, and avariety of endoscopic surgical instruments according to the presentinvention;.

FIGS. 21A to 21C illustrate a variant of an access cannula in the natureof a removable cartridge comprising internal joints and endoscopicsurgical instruments, according to an aspect of the present invention;

FIGS. 22A to 22G illustrates a variety of endoscopic surgicalinstruments engaged with an access cannula and performing a variety ofsurgical procedures on a beating heart according to an aspect of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

The features and principles of this invention may be applied, in wholeor in part, to other types of cardiac surgery preferably performedthrough a closed chest approach, and where the patients internal cardiactissue is attained through a trans-abdominal or trans-diaphragmatictunnel. Also, the features and principles of this invention may also beapplied, in whole or in part, to other endoscopic types of surgery whichrequire access to a target tissue or target organ contained within aninternal body cavity, beyond an anatomic barrier, through an accesscannula engaged with said anatomic barrier. By way of illustration, thedescription of the embodiments and variants that follows herebelow willhowever focus on applying the features and principles of the presentinvention to cardiac surgery performed on a beating heart, and morespecifically, to beating heart CABG surgery.

In the present invention, the term “thoracic cavity” will generallyrefer to the volume enclosed by the inner surface of the patient'sthorax and diaphragm. The term “pleural space” will generally refer tothe volume of a thoracic cavity less the space occupied by themediastinum and the lungs. The lungs normally occupy a large portion ofthe thoracic cavity. However, deflating a lung during a surgicalprocedure will augment the pleural space available, within whichsurgical instruments may be deployed.

By way of a general overview and with reference to FIG. 2, a surgicalincision is performed in the patient's abdomen (labelled AI), preferablyin the left upper quadrant of the abdomen. A laparoscopic cannula 499 issubsequently inserted into the abdominal incision AI, and directed intothe underlying extra-peritoneal space (labelled EPS), generally in thedirection towards the patient's head. To facilitate the displacement oflaparoscopic cannula 499 through the extra-peritoneal space, carbondioxide gas (CO2) may be channeled through a hollow longitudinal passagein laparoscopic cannula 499 (not shown) and introduced into theextra-peritoneal space through its distal tip 4. This tends to assistthe dissection of the extra-peritoneal space and laterally displace thevisceral organs (labelled VO) contained within the peritoneom (labelledPER) as the said cannula 499 is advanced within the patient's body.Proceeding in this manner, a sagittal tunnel is created spanning fromthe site of the abdominal incision to the patient's diaphragm,preferably at the left leaflet location. The diaphragm (labelled DG)constitutes an anatomic barrier that must be traversed in ordereventually obtain access to the patient's heart. A guide wire 400 isthen inserted through the center of laparoscopic cannula 499 anddirected along said cannula 499 through the length of the sagittaltunnel. Once the guide wire 400 exits from the tip 4 of cannula 499, itwill be further advanced to pierce the diaphragm and attain the pleuralspace beyond the diaphragm. The laparoscopic cannula 499 is at thispoint retrieved from the patient's body leaving behind a guidewire thatextends from outside the patient's body, into the abdominal incision,along the sagittal tunnel and beyond the pierced diaphragm into thepleural space (labelled PLS). An enlarging cannula 402 with conical tip401 and hollow longitudinal passage (not shown) is then channeled overthe guide wire 400, through the abdominal incision, through the sagittaltunnel, to attain the diaphragm at the location where said guide wire400 pierced through the diaphragm. Continuing to advance the enlargingcannula 402 over guide wire 400 will result in conical tip 401progressively distending and enlarging the hole in the diaphragminitially pierced by guide wire 400, up to a point when the cylindricalsurface 403 of cannula 402 becomes engaged with the diaphragm (FIG. 4).Progressively enlarging a hole in body tissue by advancing a cannulaconfigured with a conical tip is usually referred to in the art as aSeldinger Approach.

According to one aspect of the present invention and with reference toFIG. 4, an anatomic barrier tissue retractor in the nature of diaphragmtissue retractor 40 is subsequently inserted over the enlarging cannula402. The diaphragm tissue retractor 40 is comprised of a substantiallycylindrical hollow inner body 460, a plurality of tissue-retractingpetals 410, a substantially cylindrical translating sleeve 440, and adeployment lever 430 activated outside the patient's body. The proximalend of inner body 460 is configured with a handle portion 461 extendingoutwardly away from the longitudinal axis of said inner body 460. Thedistal end of inner body 460 is configured with a plurality ofcircumferential slots 463, which provide an opening into which a lug 412of a retracting petal 410 may pivot when said petal 410 is deployed inthe manner described below. Generally one lug 412 is required per petal410, and one slot 463 is required for each lug 412.

In their closed, non-deployed configuration, the plurality of tissueretracting petals 410 form a conical leading end profile 413 with ahollow substantially cylindrical tip 411. Tip 411 is well-suited tobeing insertable and slidable over enlarging cannula 402. Moreover, theconical profile 413 tends to facilitate the advancement of diaphragmtissue retractor 40 through the sagittal tunnel. When the diaphragmtissue retractor 40 is advanced through the patient's diaphragm, hollowtip 411 becomes inserted between the perimeter defining the piercedopening in the diaphragm and the cylindrical surface 403 of enlargingcannula 402. Each petal 410 is rotatingly engaged with the distal end ofinner body 460 through a hinge 420 disposed in lug 412. Hinge 420extends through lug 412 across its circumferential width, and alsoextends past said circumferential width into the lateral, faces definingcircumferential slot 463 in inner body 460. Petals 410, along with theirdistal end which form a part of said cylindrical tip 411, are thensimultaneously deployed through the action of lever 430. Lever 430 isengaged with handle 461 through a hinge 462. A spring element (notshown) may be installed between lever 430 and handle 461 in order tomaintain said lever and said handle apart. This minimizes the axial loadapplied to sleeve 440 thereby biasing tissue retractor 40 in itsnon-deployed, closed configuration. Deployment is achieved by depressinglever 430 sufficiently to overcome the spring load exerted from saidspring element, thereby causing sleeve 440 to axially translate througha sliding fit 441 over the outer surface of inner body 460 and towardsthe distal end of retractor 40. This entrains the engagement betweencam-like surface 445 on translating sleeve 440 and cam-like profile 415on lug 412 on each of the retracting petals 410. As a result, thetranslation of sleeve 440 induces a radially inward force on each lug412 and causes each petal to rotate about hinge 420. The distal ends ofretracting petals 410 which are engaged with the diaphragm willconsequently be entrained to move outwardly away from the axis of innerbody 460 and from one another, thereby retracting the diaphragm tissuein the process (FIG. 5A). The starting aperture in the diaphragm asillustrated in FIG. 4 is enlarged to a desired opening suitable forengagement with the distal end of an access cannula 10.

Unlike the Seldinger Approach, which generally requires a significantlength of conical profile to gradually increase the opening in ananatomic barrier by progressive insertion of a conical tip cannulabeyond said anatomic barrier, tissue retractor 40 tends to allow thesignificant enlargement of the diaphragm orifice with minimum risk ofinjury to the internal cardiac organs lying above and beyond thediaphragm. Significantly greater risk of injury would tend to result ifa Seldinger Approach was used exclusively to create an aperture of thedesired size in the diaphragm.

Referring again to FIG. 5A, while the diaphragm tissue is maintained inits retracted state by tissue retractor 40, an access cannula 10 isinserted through the center of hollow inner body 460 until its distalend 112 extends into the pleural space beyond the diaphragm. Distal end112 is configured with an anatomic barrier engaging means in the natureof a permanent weir 130. Permanent weir 130 is preferably rigid, but mayalso be made from a more flexible biocompatible polymeric material. Weir130 preferably extends around the entire perimeter of access cannula 10,and in this embodiment extends proudly above surface 113 of said cannula10. During installation of access cannula 10, weir 130 is inserted pastthe end of retracting petals 410. Deployment lever 430 is subsequentlyreleased, causing petals 410 to close slightly onto surface 113 anddiaphragm tissue to contract slightly. Tissue retractor 40 issubsequently retrieved from the patient's body thereby leaving diaphragmtissue engaged with the distal end 112 of access cannula 10, in alocation upstream of permanent weir 130.

Carbon dioxide gas (CO2) may be introduced into the pleural space andthoracic cavity either through access cannula 10 (as will be describedin greater detail below), or through a small intercostal trans-thoracicport incision. This trans-thoracic port incision does not necessitatethe cutting or spreading apart of any of the patient's ribs whichcollectively form the thoracic structure (labelled TS). Pressurized CO2tends to augment the pleural space and thoracic cavity by pushing downon the dome of the diaphragm. As such, the apex of the heart may berotated towards the patient's feet into this augmented pleural space(FIG. 3A, 3B). A sealing member, described in greater detail below, maybe incorporated within access cannula 10 to substantially maintain theCO2 pressure within the pleural space. When the diaphragm is engagedwith the access cannula 10 in a manner as described above, weir 130 actsas an axial abutment face or buttress. The pressure loads on saidcannula 10 will maintain it engaged with the diaphragm through thepermanent weir 130. Consequently, access cannula 10 may be slightlypushed out of the patient's body at the abdominal incision, leaving ashorter length of access cannula 10 engaged within the sagittal tunnel.Referring to FIGS. 3A and 3B, access cannula 10 may be configured with ademountable proximal extension tube 110. Extension tube 110 serves tofacilitate the installation of access cannula 10 into the body.Extension tube 110 also serves to facilitate the positioning andorientation of access cannula 10 relative to the patient's body.Referring to FIG. 3B, extension tube 110 is preferably detached fromaccess cannula 10 once said cannula is engaged with securing platform50. This tends to improve the ergonomics of the extracorporeal workspace. Extension tube 110 is connected to access cannula 10 through athreaded interface 111. Alternatively, extension tube 110 may also bedemountably connected to cannula 10 through a bayonet arrangement, adetented arrangement, a wedge fit or of any other like quick assemblyinterface.

Alternatively, in surgeries where CO2 gas is not introduced into thepleural space, the diaphragm may also be mechanically pulled towards thepatient's feet through the abutment face provided by weir 130 whencannula 10 is pulled by the surgeon. Those skilled in the art willappreciate that weir 130 may also be replaced by a circumferentialgroove, an expandable annular bladder, or any other like means which iscapable of engaging the diaphragm through an axial abutment face,preferably configured at the distal end 112 of access cannula 10.

Access cannula 10 may be manually held in position by a surgicalassistant during the surgical procedure. However, it is preferable tosecure said cannula in a desired substantially stable position andorientation relative to a surgical table 3 or other like fixedstationary support. Referring to FIG. 3B, proximal end 114 of accesscannula 10 is secured in place by a mechanical arm 50. Mechanical arm 50is comprised of a channel clamp 510, an articulation rod assembly 540,and a surgical table clamp 570 (FIGS. 5B and 6).

A preferred embodiment of channel clamp 510 comprises a set of threeannular discs 511, 512, 513 whose inner diameters 501, 502, 503 arepreferably equivalent. Said inner diameters are only slightly largerthan outer diameter 101 of access cannula 10 which extends over alongitudinal portion of its proximal end 114. In a non-deployed state ofclamp 510, outer diameter 101 of said cannula 10 is free to slidinglyrotate and axially translate relative to inner diameters 501, 502, and503. Discs 511, 512, and 513 are operatively engaged through annularshoulders 514 and 515 which extend laterally from side faces of disc 512and engage annular groove 506 in disc 511 and groove 505 in disc 513,respectively. Annular shoulders 514 and 515 are produced with the sameeccentricity from the centerline of diameter 502. Annular grooves 505and 506 are produced with the same eccentricity as annular shoulders 515and 514. Outer discs 511 and 513 are engaged with disc 512 andpermanently connected to each other, with matched eccentricities ofannular grooves 506 and 505, through a U-shaped block 516. Said block516 does not come into contact with the outer surface 507 of disc 512.At one location along its outer surface 507, disc 512 is configured witha lever 504 which extends radially away from said surface 507.Preferably, said lever 504 sits diametrically opposite to U-block 516when clamp 510 is in its non-deployed state. By moving lever 504 androtating disc 512 relative to outer discs 511 and 513 will radiallyoffset disc 512 relative to said discs 511 and 513 by virtue of theeccentric interface between annular grooves 505, 506 and annularshoulders 514, 515. Consequently, the three diameter 501, 502, and 503will place the engaged length of outer diameter 101 in shear, therebyachieving a desired clamping action. Outer diameter 101 will be clampedbetween a circumferential sector of diameter 502 and diametricallyopposite circumferential sectors of diameters 501, 503.

Block 516 is permanently attached to a support rod 517 that has a sphere518 at the end opposite to block 516. Nut 541 is inserted over rod 517before it becomes permanently axially retained by sphere 518, once saidsphere is permanently mounted to rod 517. Sphere 518 is brought intoengagement with socket 550 on threaded end 551 of articulation rod 543and socket surface 543 within nut 541 when said nut 541 is threaded ontoarticulation rod 543. When nut 541 is not fully tightened toarticulation rod 542, channel clamp 510 is free to rotate and pivotabout the center point of sphere 518 within the conical limits definedby the surface 542 of nut 541.

Articulation rod 543 is configured with another socket 560 at oppositethreaded end 553. Socket 560 and socket surface 552 within nut 562 arebrought into engagement with socket 571 of surgical table clamp 570 whenarticulation rod 543 is threaded into said nut 562. When articulationrod 543 is not fully tightened to nut 562, articulation rod 543 is freeto pivot about the center of sphere 571 within the conical limitsdefined by surface 563 of nut 562. Sphere 571 is permanently attached toclamp block 572 via rod 573. Nut 562 is inserted over rod 573 before itbecomes permanently axially retained by sphere 571, once said sphere ispermanently mounted to rod 573.

The location of hole 561 in nut 562 is suitably selected to attempt toprovide optimum positioning range for articulation rod assembly 540 andchannel clamp 510 with respect to the patient. Clamp block 572 issecured to a surgical table 3 by tightening at least one screw 574 withthe aid of a pivoted handle 575.

Those skilled in the art will appreciate that variations of mechanicalarms are possible without departing from the spirit of the invention.Alternatively, channel clamp 510 and any other suitable portion ofmechanical arm 50 may also be connected to a surgical robot instead ofto a surgical table 3.

In summary, mechanical arm 50 is capable of securing access cannula 10in a desired position and orientation with respect to the patient and tothe surgical table 3. Furthermore, mechanical arm 50 enablere-positioning and re-orientation of said cannula 10 during a surgicalprocedure, without having to disengage said cannula 10 from channelclamp 510. With the channel clamp 510 and nut 541 not fully tightened,the access cannula is free to rotate about its longitudinal axis,translate along its longitudinal axis, and pivot about center of sphere518. These following motion degrees of freedom are referred to as hereinas “coarse adjustment”.

In one form of coarse re-adjustment, encountered in surgery such asmulti-vessel CABG, it may be desirable to re-orient cannula 10 through arotation about its longitudinal axis, while said cannula remains engagedwith channel clamp 510 at its proximal end and with the diaphragm at itsdistal end. As described above, placing channel clamp 510 in itsnon-deployed state will easily allow said cannula to slidingly rotateabout its centerline at its proximal end, while engaged in said clamp510. Referring to FIG. 13, distal end 112 of cannula 10 may beconfigured with a bearing arrangement 140 to facilitate the saidrotation of cannula 10 relative to the engaged diaphragm tissue DG.Bearing arrangement 140 is comprised of an annular cuff 141 which isconfigured with an external annular groove 145 able to engage thepierced and retracted perimeter of an anatomic barrier, in this casediaphragm tissue DG. Annular cuff 141 is also configured with aninternal annular ridge 146 which engages and cooperates with externalannular groove 143 in surface 142 of cannula 10. Outer surface 142 ofcannula 10 and inner surface 144 of annular cuff 141 are preferablymating cylindrical surfaces allowing annular cuff 141 to be rotatinglyengaged with cannula 10. Cuff 141 is axially retained relative tocannula 10 through ridge 146. A desired rotation of cannula 10 about itslongitudinal axis will then result in a relative rotation between cuff141 and cannula 10 while the diaphragm tissue remains fixedly engagedwithin groove 145 of cuff 141. As such, by virtue of the bearingarrangement 140, the said rotation of cannula 10 tends to limit thetorsional load placed on the diaphragm and tends to limit the amount ofcircumferential slip between the diaphragm and cuff 141 along theengagement perimeter of diaphragm tissue with said cuff 141.

Outer surface 113 of access cannula 10 is substantially cylindrical andpreferably smooth in order to avoid damage to internal body tissueduring its insertion into and removal from patient's body. Referring toFIGS. 1 and 3B, the longitudinal length of cannula 10 is sufficient sothat its proximal end 114 extends from patient's body at the site of thepercutaneous surgical incision while its distal end 112 is engaged withan anatomic barrier. In this manner the proximal end 114 is exposed andmay be engaged with channel clamp 510. Alternatively, an access cannula11 may be configured with a substantially conical outer surface 12,where preferably the external diameter progressively diminishes from itsproximal end 116 towards its distal end 115 (FIG. 16A). Other liketapered configurations are also possible where the overall externaldimensions diminish from a proximal end to a distal end.

Substantially open distal end 112 consists of at least one distalopening 115. Substantially open proximal end 114 consists of at leastone proximal opening 116. Access cannula 10 is configured with at leastone hollow passageway 120 that extends substantially lengthwise alongsaid cannula, from proximal opening 116 to distal opening 115.

When access cannula 10 is deployed within the patient's body, and itsdistal end 112 is engaged with an anatomic barrier, proximal opening 116lies upstream of said anatomic barrier, while distal opening 115 liesdownstream of said anatomic barrier. As such, hollow passageway 120thereby communicates a region generally upstream of said anatomicbarrier with an internal body cavity containing target body tissue,generally downstream of said anatomic barrier, on which a surgicalintervention is intended to be performed. For example, access cannula 10may communicate an extracorporeal region (labelled ECR) upstream of thepatient's diaphragm DG, with the patient's pleural space PLS downstreamof said diaphragm DG. A surgical intervention may then be performed oninternal cardiac tissue which becomes accessible through hollowpassageway 120 of said cannula 10.

As illustrated in FIG. 5B, access cannula 10 is preferably configured toengage the diaphragm at a location close to its distal end 112 with anaim to minimize the protrusion of said distal end into the thoraciccavity. However, in certain surgeries it may be desirable to have anaccess cannula 10 which engages an anatomic barrier at a location closerto its proximal end 114, even midway between said proximal and distalends.

In some current endoscopic surgeries, the distal end of an endoscopicsurgical instrument is generally manipulated through its proximal handleportion which remains accessible to the surgeon while said endoscopicinstrument is inserted into a laparoscopy cannula. Delicate surgicalprocedures tend to be difficult to master, primarily due to the largeunsupported overhang that exists between distal end and proximal endthat is grasped by the surgeon's hand. Often times, a compromisedtactile sense also tends to result.

Although it is also possible to introduce surgical instrument throughaccess cannula 10 in a similar fashion to a laparoscopy cannula,according to one aspect of the present invention it is preferable tohave a surgical instrument engaged with an internal joint 180 disposedwithin hollow passageway 120 of cannula 10. Internal joint 180 acts as alateral support member and serves to minimize the overhang between theproximal end and the distal end of a surgical instrument engagedtherein. Internal joint 180 is free to move when engaged with a surgicalinstrument prior to being secured into a fixed position through atightening member 181. When said internal joint is secured, it may serveto retain a surgical instrument engaged therein in a fixed position andorientation relative to access cannula 10. As will be explained furtherbelow, internal joint 180 may also act as a fulcrum member. By virtue ofthe fulcrum member, a surgeon input applied to a surgical instrument atits proximal end will be transferred to its distal end, whereby theresulting movement of the distal end may be of an equal magnitude,greater magnitude, or a lesser magnitude relative to said surgeon input.

Referring to FIGS. 14A and 14B, at least one internal joint is providedwithin the at least one hollow passageway 120 in access cannula 10.Internal joint 180 protrudes away from the internal surface of hollowpassageway 120 so that it may become engaged with a portion of asurgical instrument. Internal joint 180 is comprised of a substantiallyspherical collet 182, a yoke 186, and a tightening member 181. Saidcollet 182 is configured with a cylindrical bore 184 whose centerlinecoincides with the center of spherical collet 182. Said collet 182 isconfigured with at least one split gap 183 extending from its outerspherical surface to inner cylindrical surface defining bore 184. Saidsplit gap 183 preferably extends throughout the entire longitudinallength of said bore 184. Alternatively, collet 182 may be configuredwith a plurality of like split gaps as those skilled in the art willappreciate. Collet 182 is preferably made from a substantially elasticmaterial.

A surgical instrument may first be inserted into bore 184 of sphericalcollet 182, and the resulting assembly thereof transversely installedinto yoke 186. In this respect, internal joint 180 is considered an“open-ended design” since it permits a surgical instrument to betransversely mounted into engagement with inner joint 180.Alternatively, spherical collet 182 may first be engaged into yoke 186and a surgical instrument subsequently installed axially through bore184 thereof. Yoke 186 is configured with a spherical seat 185. Extensionrod 189 is provided with an anti-rotation flat 187 which cooperate withopening 118 when said rod is inserted through said opening. Tighteningmember 181 engages with thread 188 on the distal end of extension rod189.

Collet 182 simultaneously cooperates with socket surface 119 of accesscannula 10 and spherical seat 185 of yoke 186, when internal joint isfully assembled. Applying a torque to tightening member 181 will entrainseat 185 into light contact with spherical collet 182, and sphericalcollet 182 into light contact with socket surface 119. At this point, asurgeon manipulation (input) applied to the proximal end of surgicalinstrument will be easily sufficient to set into relative motionspherical collet 182 relative to socket surfaces 185 and 119 (freestate). Applying a greater torque to tightening member 181 will augmentthe friction between external surface of collet 182 and said sphericalsurfaces 185 and 119, thereby providing a greater resistance to thesurgeon input (constrained state). Increasing the tightening torquestill further will compress spherical collet 182. The resultingcompression force is transferred to the portion of a surgical instrumentengaged within bore 184 as a clamping load by virtue of split gap 183,thereby securing the entire assembly of components defining internaljoint 180 (locked state). Relieving the tightening torque on tighteningmember 181 will relieve said clamping load on said surgical instrumentand relieve the friction between socket surfaces 119, 185 and sphericalcollet 182. The internal joint 180 resumes its free state, aided in partby the elastic nature of collet 182. At this point, said surgicalinstrument is once again free to be re-positioned and reoriented withrespect to access cannula 10 through internal joint 180.

The portion of a surgical instrument engaged within bore 184 ispreferably of circular cross-section. The internal joint 180 providesthe following motion degrees of freedom when engaged in “free state”with a surgical instrument: translation of said surgical instrumentalong centerline of bore 184, rotation of said surgical instrument aboutcenterline of bore 184, pivoting of said surgical instrument about alongitudinal axis through extension rod 189, pivoting of said surgicalinstrument about an axis perpendicular to longitudinal axis throughextension rod 189 and simultaneously perpendicular to centerline of bore184. Open-ended internal joint 180 allows 4 motion degrees of freedomand may be secured through tightening member 181 which is situated onthe exterior of access cannula 10. These motion degrees of freedombetween a surgical instrument and access cannula 10 are referred toherein as “fine adjustments”. Alternatively, a surgical instrument withone or more integral spherical bosses along its longitudinal axis may beinserted into internal joint 180 in place of spherical collet 182.

Open-ended internal joints permit the substitution of surgicalinstruments engaged with said joints, without having to disrupt thecoarse adjustment of the surgical set-up.

Other variations of internal joints may be configured as those skilledin the art will appreciate, some with fewer motion degrees of freedom.For instance, a joint that only allows translation along thelongitudinal axis of a surgical instrument, a joint that only allowsrotation of a surgical instrument about its centerline, a joint thatonly allows pivoting about one axis, and any combination thereofrepresent potential embodiments.

A close-ended variant of the internal joint 180 is illustrated in FIGS.14A and 14B. Close-ended joint 150 is preferably employed to engagesurgical instruments that form an integral permanent assembly with anaccess cannula. Alternatively, in non-permanent assemblies, close-endedjoints may also be employed with surgical instruments havingcross-sectional dimensions inferior to bore 151, which are thereforecapable of being axially inserted through said bore.

FIG. 8A illustrates another variant of an open-ended internal joint 170.Internal joint 170 is comprised of two jaws 174, 175 which arepivotingly engaged through hinge member 173. Said jaws cooperate toclamp a surgical instrument at open-ended bore 176 when wedge 172 isretracted through hollow boss 171 through its connection to threaded rod177. Applying a tightening torque to tightening member 181 will entrainthreaded end 177 to move axially through hollow boss 171. Prior toapplying a securing torque to said member 181, jaws 174, 175 are free torotate about the centerline of threaded rod 177. Inner joint 170provides the following motion degrees of freedom: translation of asurgical instrument along the longitudinal axis of bore 176, rotation ofa surgical instrument about centerline of bore 176, and rotation aboutcenterline axis of rod 177.

Another close-ended, multi-degree of freedom variant of an internaljoint is illustrated in FIG. 8B. Internal joint 190 is comprised of twoC-shaped jaws 191 and an articulation cylinder 194. Each jaw 191 has athreaded rod 197 extending along its longitudinal axis. Each jaw 191 hasa substantially hemi-cylindrical surface 193 defined by an axisperpendicular to its longitudinal axis. Each jaw has a lateral member165, offset from longitudinal axis of said jaw, connecting threaded rod197 to surface 193. When jaws 193 are assembled with articulationcylinder 194, threaded rods 197 extend in opposing directions through acommon centerline, each of surfaces 193 lie diametrically opposed, andeach of lateral members 165 are laterally opposed. Articulation cylinder194 is laterally trapped between said lateral members 165 and radiallyengaged with each of the hemi-cylindrical surfaces 193. A cylindricalbore 195, perpendicular to the centerline of cylindrical outer surfaceof articulation cylinder 194, is provided to receive a portion of asurgical instrument axially inserted therein. The inner surface ofcylindrical bore 195 is interrupted by at least one substantiallylongitudinal split 196.

When assembled jaws 193 are assembled, outboard surfaces of lateralmembers 165 form a partial interrupted cylinder whose centerline iscoincident with centerline of threaded rods 197. The assembly comprisedof jaws 191 and articulation cylinder 194 is transversally inserted intobore 192 of access cannula 10. Threaded rod 197 of one of the jaws 191is sufficiently threaded into boss 199 of cannula 10 such thatcenterline of bore 195 is substantially aligned with longitudinal axisof access cannula 10. At least a portion of said cylinder formed byoutboard surfaces of lateral members 165 cooperates with bore 192 asinternal joint 190 rotates within said bore 192. As internal joint 190rotates within bore 192 threaded rod threads or unthreads itself intoboss 199. Said bore 192 is mostly open towards the center of accesscannula 10 providing substantially unrestricted motion to a surgicalinstrument engaged in bore 195 of articulation cylinder 194. Washer 198is inserted between access cannula 10 and tightening member 181. Atightening torque applied to tightening member 181, will entrain intocontact said hemi-cylindrical surfaces 193 with outer diameter ofarticulation cylinder 194. A substantially diametrical clamping loadwill be applied to outer diameter of articulation cylinder 194. Theresulting compression force is transferred to the portion of a surgicalinstrument engaged within bore 195 by virtue of split 196, therebysecuring the entire assembly of components defining internal joint 190.

Internal joint 190 allows the following motion degrees of freedom:translation of a surgical instrument along centerline of bore 195,rotation of a surgical instrument about centerline of bore 195, pivotingof a surgical instrument about centerline through bore 192, pivoting ofa surgical instrument about an axis perpendicular to centerline throughbore 192 and simultaneously perpendicular to centerline of bore 195.Once the desired position and orientation of a surgical instrument isachieved, this fine adjustment is secured through tightening member 181situated on the exterior of access cannula 10.

Internal joints 150, 170, 180, and 190 may engage the particularsurgical instruments according to the present invention, and alsoexisting endoscopic instruments, laparoscopic instruments, cardiacsurgery instruments and other like instruments.

Internal joint 180 acts as a fulcrum point allowing the movement at theproximal end of a surgical instrument (surgeon input) to be transferredthrough internal joint 180 to a corresponding linked movement at thedistal end of said surgical instrument. For the purposes ofillustration, FIG. 20 schematically represents access cannula 10 as acylinder. An internal joint is located within access cannula 10 at adistance X from proximal open end 116 and at a distance Y from thecenter line of access cannula 10. A surgical instrument is schematicallyrepresented as a line (labelled “SI”). PSI represents the surface areawithin which a surgeon may position a proximal point P of a surgicalinstrument, when said point P is held at a fixed distance from thecenter of the internal joint. When point P is held at a closer distancefrom the center of internal joint, PS2 is generated. DS1 and DS2represent the surface areas within which the distal point D of asurgical instrument is maintained during proximal manipulations of pointP within PS1 and PS2, respectively. The size and geometry of proximalsurfaces PS1 and PS2 and of distal surfaces DS1 and DS2 are a functionof the specific geometry of access cannula 10, the number of motiondegrees of freedom offered by the internal joint, the range of motion ofsaid offered motion degrees of freedom, the length of surgicalinstrument SI, and the distance between proximal point P on surgicalinstrument SI and internal joint. If a surgeon's input is applied toproximal point P and is limited to the confines of proximal surface PS1,distal point D will then be limited to the confines of distal surfaceDS1. As illustrated in FIG. 20, since proximal surface PS1 is largerthan corresponding distal surface DS1, a surgeon input applied at pointP will result in a scaled down output at point D. Alternatively, if asurgeon's input is applied to proximal point P and is limited to theconfines of proximal surface PS2, distal point D will then be limited tothe confines of distal surface DS2. Since proximal surface PS2 issmaller than distal surface DS2, a surgeon input applied at point P willresult in a scaled up output at point D. Therefore, a surgeon inputapplied extracorporeally to a proximal end of a surgical instrument willentrain a linked movement of a distal end within an internal bodycavity, downstream of an anatomic barrier by virtue of an internaljoint.

Hollow passageway 120 may be partitioned to define at least one otherhollow passageway extending from proximal open end 116 to distal openend 115. Two such hollow passageways 121, 122 are illustrated in FIG.8A. At least one such passageway will be configured with an internaljoint such as 150, 170 180, 190 or other like joint or variant thereof.In other surgical set-ups, it may be preferable to have at least oneinternal joint in each of the said hollow passage ways 121, 122. Therelative cross-sectional areas and cross-sectional geometries ofpartitioned hollow passageways may be tailored for the specific surgicalinstrument said passageway will be engaged with, or the specificsurgical procedure that will take place in said passageway. In general,a hollow passageway is intended to be engaged with a surgicalinstrument. In configurations of access cannulas comprising more thanone internal joint, said internal joints may each be disposed at adifferent location along the longitudinal axis of said cannula, and eachbe disposed at a different angular orientation relative center oflongitudinal axis.

In addition to hollow passageways, access cannula 10 may be configuredwith one or more access lumens 125 (FIGS. 8A, 8B, 14A). Access lumensprovide a substantially confined channel into which a surgical aid,fluid, or gas may be engaged or introduced.

Each access lumen may serve a designated purpose during at least a partof a surgical procedure or may be specifically designed to engage aparticular surgical aid for the duration of the surgical process. Anaccess lumen may be integrally produced with access cannula 10 as acored passage in the fabrication process. Alternatively, an access lumenmay be formed from a channel member which is subsequently fastened toaccess cannula 10, preferably within one of its hollow passageways.Access lumen may be fastened in a demountable or permanent manner tosaid access cannula 10. Access lumens have at least one entry point 126and at least one exit point 127. Generally, access lumens extend fromproximal open end 116 to distal open end 115 of cannula 10. However,they may extend for only a part of the longitudinal length of cannula10. In either case, entry point 126 is generally located upstream ofanatomic barrier and 127 is generally located downstream of anatomicbarrier. This provides a communicative channel from a region upstream ofsaid anatomic barrier (most often the extracorporeal space ECS) to aninternal body cavity such as the pleural space PLS.

In another variant, an access lumen may extend for only a part of thelongitudinal length of cannula 10, where entry point 126 and exit point127 are either both upstream of anatomic barrier or both downstream ofan anatomic barrier.

In another variant, an access lumen 129 is configured with an exit point127 leading into the at least one hollow passageway of access cannula 10(FIG. 16A).

In another variant, access lumen does not longitudinally along length ofaccess cannula 10, but may be of a helical configuration along thesurface of hollow passageway 120.

In yet another variant, access lumen 128 may be configured with acircumferential segment acting as a manifold for a plurality of exitholes 127 (FIGS. 16A, 16B). This configuration may be preferable forintroducing a surgical gas such as CO2 into the pleural space.

Designated access lumens may be provided for engaging following surgicalaids, or channeling the following fluids or gases: a malleable arm withsmall atraumatic clip at distal end thereof, a fiber optic bundle forillumination of surgical site, a surgical camera lens, CO2 pressurizedgas, saline solution, pharmacological agents, a suction line, acatheter, a cannula, a laser probe, a doppler ultrasonography probe, asensor, or any other like surgical aid, fluid or gas.

A visioning system may be housed in an access lumen to allow the surgeonto vision the substantially closed pleural space (or thoracic cavity)during the surgical procedure performed therein. A visioning system ispreferably comprised of stereoscopic camera lenses. In another variant,only some of the components of the vision system may be provided in anaccess lumen while other complimentary components may access thesubstantially closed thoracic cavity through intercostal access ports.Also in this manner separate vision cameras may be configured, one in anaccess lumen of access cannula 10, another in an intercostal portincision, thereby allowing the surgical procedure within the thoraciccavity to be visioned through one or more different visual perspective.

Access cannula 10 may be configured with a combination of internaljoints, partitioned hollow passageways, and a number of access lumens.For instance, FIG. 8A illustrates a partitioned access cannula 10 withone open-ended internal joint 170, two hollow passageways 121, 122 andtwo access lumens 125. FIG. 8B illustrates a partitioned access cannula10, with one close-ended internal joint 190, two hollow passageways 121,122, and a plurality of access lumens 125. FIG. 14A illustrates apartitioned access cannula 10 with a plurality of close-ended internaljoints 150 and a plurality of open-ended joints 180, two hollowpassageways 121, 122 and two access lumens 125. Other combinations arealso possible.

Access cannula 10 may be configured with a provision for a sealablehollow passageway. A seal member 70 may be provided to span in asubstantially transverse manner across a hollow passageway. Seal member70 will preferably span across hollow passageway at a location betweenproximal open end 116 and distal open end 115 of said cannula 10. Sealmember 70 may also span across proximal open end 116 or distal open end115.

Seal member 70 provides a substantial seal and substantially confinesthe ambient conditions present within the internal body cavity andwithin a hollow passageway downstream of said seal member, from theambient conditions present in the hollow passageway upstream of saidseal member and externally beyond the proximal open end 116 of saidaccess cannula 10. For instance, in surgeries where CO2 gas will beintroduced into the pleural space PLS, the pressurized volume presentwithin the pleural space and within a hollow passageway of accesscannula 10 downstream of seal member 70 is substantially confined fromthe extracorporeal ambient conditions present upstream of said sealmember. Evidently, to maintain said pressurized volume all hollowpassageways must be provided with a seal member 70, and all accesslumens must also be substantially sealed either with a plug memberengaged at entry point 126 or exit point 127, or by the obstructioncreated by a surgical aid engaged within said access lumen, or by a sealmember similar to seal member 70.

Seal member 70 may also be used to shield a portion of a hollowpassageway and internal joints located upstream of said seal member fromblood and other like body fluids present within the internal body cavityand downstream of said seal member. In a partitioned access cannula, aseal member may be provided in just one of the hollow passageways, or inall said passageways.

FIG. 7 illustrates a conformable elastic seal membrane 701. Sealmembrane 701 is provided with one or more sealable ports in the natureof elastic nipple 702 through which a variety of surgical instrumentsmay be easily inserted either before or during surgery. Elastic membrane701 and nipple 702 will conform to suit the angle in which the shaftportion of a surgical instrument will be oriented within said nipple.This tends to provide substantially unconstrained motion of the surgicalinstrument within access cannula 10. Further, elastic nipple 702provides a compliant through-passage that stretches and shrinks toaccommodate surgical instruments with different dimensions. Elasticnipple 702 is biased towards a closed, sealed position wherein saidvariable size through-passage is not engaged with a surgical instrument.Said nipple 702 is movable to an open, sealed position by virtue ofinserting a surgical instrument therethrough. As such, elastic nipples702 provide a substantial seal in both closed and open position.

FIGS. 14B and 14C illustrate a conformable, elastic bellows-type seal730. Seal 730 is comprised of a plurality of elastic nipples 732.Nipples 732 are self-energizing in that a pressure gradient will keepnipple closed and substantially non-flowing when surgical instrument isnot engaged therein. When a surgical instrument is inserted in saidnipple 732, the self-energizing effect will keep nipple perimeter 733 incontact with surgical instrument. Pressure gradient for self-energizingeffect requires the pressure downstream of nipple perimeter in region734 to be greater than pressure upstream of seal in region 735. Asillustrated, seal 730 is self-energizing when pressurized CO2 isintroduced into the pleural space. Seal 730 may be reversed to cater foropposite pressure gradients. Nipple 732 provides a substantial seal.

Seal 730 is configured with a plurality of substantially concentricannular folds 731 originating from the center of each nipple 732. Saidplurality of annular folds 731 act as a radial bellows. A displacementof nipple 732 entrained by a movement of a surgical instrument relativeto cannula 10, will compress annular folds 731 in the direction of saiddisplacement of nipple 732. By virtue of its elastic material propertiesand its radial bellows configuration, seal 730 tends to allowsubstantially unconstrained motion of a surgical instrument withinaccess cannula 10.

FIGS. 16A and 16B illustrate an elastic membrane-type seal 720 providedwith one or more sealable ports in the nature of a plurality ofoverlapping leaflets 724 through which a variety of surgical instrumentsmay be inserted. Said leaflets 724 are biased in a closed, not deflectedorientation 721 thereby providing a substantial seal. When instrument isinserted through said sealable port, leaflets 724 are deflected 722 butremain in substantial contact with the shaft portion 723 of a surgicalinstrument. As such, leaflets 724 provide a substantial seal in bothclosed and deflected position. Leaflets will engage with shaft portion723 to a varying extent depending on the orientation of said shaftportion 723 through said leaflets 724. All leaflets will be engaged toat least some extent, throughout the complete range of orientations saidshaft portion 723 is capable of assuming in order to maintain asubstantial seal throughout said range. By virtue of its elasticmaterial properties and its leaflet configuration, seal 720 tends toallow substantially unconstrained motion of a surgical instrument withinaccess cannula 10.

By way of a general overview, FIG. 1 illustrates a surgical apparatusaccording to a first embodiment of the present invention. The surgicalapparatus is comprised of a surgical arm 50, an access cannula 10, aheart manipulator 20, and a coronary stabilizer 30. Thoracoscopicsurgical instruments 60 are provided with which the invention may beused. Said instruments 60 are deployed intercostally and tend to notrequire spreading of the patient's ribcage. Access cannula 10 ispreferably deployed and engaged with the patient's diaphragm throughdiaphragm tissue retractor 40 in a manner described above.

Referring to FIG. 7, heart manipulator 20 and coronary stabilizer 30 arepreferably engaged with access cannula 10 through an internal joint 190(or alternatively 150, 170, or 180), in a manner already described withgeneral reference to a surgical instrument.

Once the coarse adjustment has been performed and access cannula 10 hasbeen secured to channel clamp 510 of surgical arm 50 in the desiredposition and orientation relative to the patient's body, the heartmanipulator 20 is preferably deployed first.

Heart manipulator 20 engages a portion of the surface of a beatingheart, preferably in the vicinity of the apex, through a negativepressure suction force. Said manipulator 20 serves to position andorient the patient's heart within the thoracic cavity. While it isengaged with the apex of the patient's heart, heart manipulator 20 maybe secured through internal joint 190 in a desired position andorientation relative to access cannula 10 (fine adjustment), therebyalso securing a position and orientation of the patient's heart relativeto said access cannula 10.

Heart manipulator 20 is comprised of a hollow shaft member 220, a heartcontacting member 200 and a handle 240. Shaft member 220 is preferablycylindrical in cross-section and hollow thereby configuring conduit 223along its entire length. Shaft member 220 is engaged at its distal openend 226 with heart contacting member 200 and at its proximal open end224 with a negative pressure source 227 through barb fitting 221.Conduit 223 communicates negative pressure suction to the heart contactmember 200 through its connection with a negative pressure source atbarb fitting 221. Heart manipulator 20 is manipulated by surgeon throughhandle 240 which extends beyond proximal open end 116 intoextracorporeal space once heart manipulator is engaged in internal joint190. Handle 240 is preferably detachable through a sliding fit betweenouter surface 225 and bore 245 in said handle. This sliding fit allowssaid handle to be positioned at a desired location along shaft member220. When detachable handle 240 is removed from heart manipulator 20,shaft member 220 may be axially inserted into a close-ended internaljoint such as 190 prior to deploying access cannula 10 into engagementwith diaphragm. Alternatively, heart manipulator 20 may be transverselyengaged into an open-ended internal joint such as 180, 170 even afterthe access cannula 10 has been engaged with the diaphragm.

Heart contacting member 200 is comprised of a substantially conicalelastic sheath 204, detachably mounted to shaft member 220 through abarb fitting interface formed by mating members 202 and 222. Said sheath204 may be produced from any suitable polymeric material approved forsurgical use. Sheath 204 may be designed to have variable elasticproperties by virtue of its variable thickness or by virtue of itsvariable composition during fabrication. Reinforcement fibers orstructural ribs 201 may also be used in the fabrication of sheath 204 tobias its elasticity along certain axes. This is especially beneficialwhere the shaft member 220 is rigid, whereby elastic sheath 204 acts asa buffer in elastic gradient between said rigid member 220 andsubstantially non-rigid heart surface or non-structural membrane-likepericardium tissue if said heart manipulator is engaged with pericardiumtissue. This buffer in elastic gradient may encourage the said heartsurface or said pericardium tissue to remain in compliant contact withtissue-engaging perimeter 205 of said sheath.

The open area perimeter 205 is configured with a tapered and beveledterminal edge in the nature of a deformable skirt 203. This deformableskirt 203 achieves a substantially compliant seal perimeter attissue-engaging perimeter 205, capable of engaging the surface of theheart or pericardium tissue throughout a range of spatial orientationswhich the said heart or said pericardium tissue may assume relative toshaft member 220. The deformable skirt 203 provides readjustment of thesubstantially planar surface formed by tissue-engaging perimeter 205depending on the direction of application of tensile retraction loadsapplied to and reacted by the said heart or said pericardium tissue. Atensile retraction load applied to said heart or said pericardium tissuein a direction substantially parallel to the axis of shaft member 220distorts the beveled edge of deformable skirt 203 equally around thetissue-engaging perimeter 205, in an inward direction towards the centerof said tissue-engaging perimeter 205. If a tensile retraction load isapplied to said heart or said pericardium tissue in a skewed directionrelative to the axis of shaft member 220, the beveled edge of skirt 203will distort unevenly around the tissue-engaging perimeter 205 in afashion that the substantially planar surface formed by tissue-engagingperimeter 205 is now oriented substantially perpendicular to thedirection of application of said manipulation force or substantiallyperpendicular to the heart reaction force to imposed retraction loads.

Alternatively, heart manipulator may be comprised of a plurality ofconical elastic sheaths 204 configured in a manifold assembly andconnected to a common hollow shaft member.

Alternatively, a heart contact member comprising a substantially conicalnon-flowing static suction cup made from a flexible polymeric materialmay be utilized.

Referring now to FIGS. 15A to 15D, a portion of a beating heartcontaining the apex is engaged with heart contact member 200 and isschematically represented as APX. For the purposes of illustration, thedifferent surfaces of the beating heart are identified by four arbitrarymarkers: “A” marks a point on the anterior surface of the heart; “R”marks a point on the right lateral surface of the heart; “P” marks apoint on the posterior surface of the heart; and “L” marks a point onthe left lateral side surface of the heart. Access cannula 10 isschematically illustrated as a cylinder in end view. For the purposes ofillustration, three arbitrary markers “X”, “Y”, “Z” are identified onthe perimeter of access cannula 10. Heart manipulator 20, and morespecifically heart contact member 200 is represented by itstissue-engaging perimeter 205. Internal joint 180 is reserved forcoronary stabilizer 30 (not shown). Heart manipulator 20 is engaged in asimilar internal joint (not shown), which for the purposes of thisillustration is disposed diametrically opposite to said internal joint180 about the centerline of access cannula 10.

FIG. 15A illustrates access cannula 10 secured in a desired position andorientation relative to surgical arm 50 (coarse adjustment), whereinternal joint 180 is located at top dead center (looking into cannula10). When the beating heart is engaged with heart contact member 200,and the heart manipulator 20 is engaged in internal joint 180, saidinternal joint in its free state will allow the center of the heartcontact member (labelled “CX” in FIG. 9) to be positionable anywherewithin surface area AHC (area within circle labelled AHC). The size andshape of AHC is here only schematically represented as a circular area.AHC generally increases in size and its shape may vary as the distancefrom point CX to the center of spherical collet 182 of internal joint180 increases. This is representative of a heart contacting member 200being extended further into the pleural space PLS beyond the distalopening 115. Now if this variable AHC area is integrated over the rangethat said heart contacting member 200 is capable of extending beyond thedistal opening 115, a volume results within which point CX may bepositionable. The actual size and shape of AHC (and the resulting saidvolume) is a function of many parameters. Among these: the specificgeometry of an access cannula, the number of motion degrees of freedomoffered by a design of an internal joint, the range of motion of saidoffered motion degrees of freedom, and the distance between point CX andsaid internal joint. As a result of the foregoing, the apex of a beatingheart when engaged with heart contacting member 200, may also bepositionable within a considerable volume.

As illustrated in FIG. 15B, when access cannula 10 is re-oriented withinchannel clamp 510 through a 90 degree counterclockwise rotation aboutits centerline, surface area AHC orbits around the centerline of accesscannula 10 while rotating 90 degrees counterclockwise. Nominal orbittrajectory is identified as ORB. The beating heart, represented by APX,orbits relative to the centerline of access cannula 10 but does notrotate. During this coarse readjustment, internal joint 180 is in itsfree state such that shaft member 220 is free to rotate about itscenterline while tissue-engaging perimeter 205 remains engaged with saidbeating heart. By rotating access cannula 10 in the manner justdescribed, all surfaces of the heart are generally accessible bycoronary stabilizer 30 which may be deployed through the portion ofhollow passageway 124 not occupied by heart manipulator 20. FIG. 15Aillustrates the surgical set-up well suited to access the anteriorsurface of a beating heart; FIG. 15B a surgical set-up well suited toaccess the right lateral surface of a beating heart, FIG. 15C a surgicalset-up well suited to access the posterior surface of a heart, and FIG.15D a surgical set-up well suited to access the left lateral surface ofa beating heart.

Referring to FIG. 10, the coronary stabilizer 30 is comprised of threemain subassemblies: a proximal extracorporeal control section 380; adistal heart-contacting section 300 deployed within the thoracic cavity;and a connector section 390 for transmitting a surgeon input from saidcontrol section to said heart-contacting section.

The control section 380 comprises a securing bolt 385, a multi-socketcradle 389, an annular brace 387, an first adjustment dial 371, and asecond adjustment dial 331. Cradle 389 is configured with three lobes388, only two of which are visible in FIG. 10. Each lobe 388 isconfigured with a spherical socket (not shown) that engages a sphericalend (not shown) disposed on each of the three articulation transmissioncables 340. Said spherical ends may be permanently engaged with saidspherical sockets in cradle 389 by flaring the socket perimeter aroundthe spherical end. Alternatively, said spherical ends may be demountablyengaged with said spherical sockets by virtue of a “snap in” design.Inner rod 386 is configured with three longitudinal channels 384 thateach serve to house one of the transmission cables 340.

The cradle 389 is also configured with a central spherical socket (notshown) to engage and cooperate with a substantially spherical end (notshown) on the proximal extremity of inner rod 386. The perimeter whichdefines the opening of said central spherical socket is locally flared athree locations to create a perimeter with three flared edges. Saidsubstantially spherical end of inner rod 386 is configured with threeflats that allow it to be insertable past the said three flared edges ofcentral spherical socket in cradle 389. Cradle 389 is subsequentlyrotated with respect to centerline of inner rod 386, such that saidflared edges on central spherical socket engage with a portion of thespherical end of rod 386 not interrupted by said flats. This results incradle 389 and inner rod 386 being movably connected while beingpivotingly engaged. This orientation of cradle 389 relative to inner rod386 is maintained when the spherical ends of each of the threetransmission cables 340 are engaged with the spherical sockets in lobes388 while said cables are located in channel 384.

The center socket in cradle 389 is pierced by a threaded hole (notshown), at its topmost point, to cooperate with securing bolt 385.Applying a torque on said bolt results in a force being exerted on thespherical end of rod 386, thereby securing said spherical end againstthe three flared edges of cradle 389. This results in a locked assembly.Loosening bolt 385 permits sliding at the spherical interface betweenspherical end of rod 386 and central socket of cradle 389.

Transmission cables 340 extend from a control section 380 to aheart-contacting section 300 through a connector section 390. Saidtransmission cables slide in a substantially closed passage formed bylongitudinal channel 384 and the inner diameter of hollow proximal shaft360. Said transmission cables 340 slide in a similar substantiallyclosed passage formed by a longitudinal channel (not shown) in distalinner rod 352 and inner diameter of hollow distal shaft 350. By pivotingthe cradle 389 relative to spherical end of rod 386, each of thearticulation transmission cables 340 will slide within its respectiveclosed passage, a variable and different amount based on the relativeorientation of cradle 389 relative to inner rod 386. By virtue of itsconnection with each of the transmission cables 340, this variable anddifferent amount of sliding experienced by each of the three cables willallow plate member 320 to assume a multitude of different spatialorientations. An annular brace 387 is inserted over inner rod 386serving to retain cables 340 within their longitudinal channel 384 atthe proximal control section 380. A similar brace may also be installedat the distal heart-contacting section 300.

Each of the transmission cables 340 is configured with a distalspherical end 341. Each of said spherical end 341 is engaged to a quickassembly/disassembly interface socket 321 on plate member 320, therebyserving to connect heart-contacting section 300 with connector section390.

Heart-contacting section 300 is comprised of at least one contact member301, a shaft member 323, a plate member 320, and a bushing 322. Contactmember 301 is configured by two elongated contact arms 302 definingtherebetween an arterial window 304. Two arms 302 are preferablysubstantially parallel and configure a substantially planar contactsurface. Two contact arms 302 may be provided with a textured undersidesurface 305 to improve adherence with the surface of a beating heartwhen placed in contact with said heart.

Contact member 301 serves to immobilize a portion of the surface of thebeating heart proximate to a target coronary artery that will require asurgical intervention, such as an anastomosis. Contact arms 302 areshaped to be capable to press against the surface of a beating heart.Said arms are positioned on the said surface of a beating heart in sucha manner as to straddle the target coronary artery proximate to thearteriotomy site within the arterial window 304. Contact member 301 isrigidly connected to shaft member 323. Bushing member 322 is rigidlyconnected to plate member 320 on opposite side of sockets 321. Shaftmember 323 is rotatingly engaged with bushing member 322.

Axis B is the longitudinal axis of rotation of shaft member 323. Axis Eis parallel to the plane containing plate member 320 and is normal toAxis B. Axis D is the longitudinal axis of distal shaft 350. Axis Dsubstantially intersects Axes B and E.

The substantially planar contact surface of contact member 301 may bepositioned and oriented with respect to distal shaft 350 through platemember 320 which is in turn positioned and oriented through itsconnection with transmission cables 340 which respond to a surgeon inputapplied at cradle 389. This results in two motion degrees of freedom.The first motion degree of freedom is a rotation about Axis E whichcauses contact member 301 to tilt relative to distal shaft member 350.The second motion degree of freedom is a rotation about Axis B whichcauses contact member 301 to yaw relative to distal shaft member 350.

The coronary stabilizer 30 may also be provided with an additionaladjustment that allows distal shaft member 350 to pivot relative toproximal shaft member 360 about Axis A. Axis A is the centerline throughhinge 361. This additional adjustment allows the heart contacting member301 to be set in a position and orientation substantially offset fromthe longitudinal axis of access cannula 10, when said contact member 301extends distally beyond the distal open end 115 of said access cannula.This additional adjustment is especially useful in adjusting theorientation and position of the contact member 301 relative to accesscannula 10, in a manner that tends to improve the presentation of saidcontact member on the target arteries located on the wider portions of abeating heart. This improved presentation of contact member 301 on thesurface of the beating heart proximate to the target coronary arteryalso tends to improve the efficacy of the subsequent imposedimmobilization by said contact member. The rotation of dial 371 entrainsthrough its engagement with a sliding member (not shown) within theproximal shaft 360 the translation of elbow 370 within slot 362. As aresult, shaft 350 pivots about hinge 361 to a desired angle. Theeccentricity of distal hinge 351 with respect to proximal hinge 361results in a bias direction of pivot when a torque is applied toadjustment dial 371. This results in a fourth motion degree of freedomnamely pivoting about Axis A which is coincident with centerline ofhinge 361.

Inner rod 386 is rotatingly engaged with proximal shaft 360 along itslongitudinal Axis C. Inner rod 352 is rotatingly engaged with distalshaft 350. Rotating cradle 389 relative to proximal shaft 360 about axisC entrains a rotation of plate member 320 by virtue of the simultaneousengagement of cables 340 with the sockets in lobes 388 of cradle 389,the longitudinal channels 384 in inner rod 386, and the interfacesockets 321 in plate member 321. This results in a fourth motion degreeof freedom namely, rotation about axis D which allows contact member 301to revolve about said axis relative to distal shaft member 350.

Coronary stabilizer 30 may also be provided with an additionaladjustment enabling the rotation of contact member 301 about Axis B.This allows the angular orientation of the arterial window 304 withrespect to shaft 350, in order to more adequately access target arteriesthat are disposed in a diagonal orientation with respect to the longaxis of the heart. Rotation of dial 331 acts on a fourth returntransmission cable 330, which in turn applies a torque on shaft 323attached to contacting member 301. Shaft 323 rotates within bushing 322.This results in an increased range for the second motion degree offreedom, that is, rotation about axis B.

Coronary stabilizer 30 tends to react mostly the local forces exerted bythe underlying pulsating myocardium that it immobilizes. The loadsassociated with positioning and orienting the entire beating heartwithin the thoracic cavity are reacted mostly by the heart manipulator20.

To achieve a substantially bloodless surgical field during beating aheart bypass surgery, heart contacting member 301 is configured with atleast one wire attachment pedestal 310. As illustrated in FIG. 10, foursuch pedestals 310 are provided, two pedestal 310 on each of contactarms 302 disposed on opposite sides of arterial window 304. Saidpedestals 310 serve to engage a vessel occluding wire 303, preferably asilicone elastomer vascular loop. One said wire circumvents the targetartery upstream of the grafting site while the other circumvents thetarget artery downstream of the grafting site. The two loose ends ofeach said wire 303 are subsequently engaged in opposing pedestals 310located on opposite contact arms 302. As such, the target artery issubstantially snared by the deployment of said wire 303 tending toocclude said artery and create a substantially bloodless surgical field.The said pedestals 310 are each provided with at least one slit whichtends to achieve a light-tight anchoring of vessel occluding wire 303.Light-tight anchoring will retain said wire 303 engaged with said slitin pedestal 310 up until a threshold tension is applied to the occludingwire 303. At this point, said wire will begin to slip through said slit.This tends to favor non-traumatic disengagement of said wire from saidslit in the eventuality of an unwanted slippage of the coronarystabilizer 30 or an undesirable movement of the beating heart. Saidslits in pedestals 310 allow a surgical wire 303 in the nature of asilicone elastomer vascular loop engaged therein to be pulled throughsaid slit from a first engaged position to a second engaged positionwithout having to disengage said wire from said slit.

When proximal shaft member 360 of coronary stabilizer 30 is engaged ininternal joint 190 (or like joint 180), said internal joint in its freestate will provide four motion degrees of freedom. That is: translationof proximal shaft member 360 along centerline of bore 195, rotation ofproximal shaft member 360 about centerline of bore 195, pivoting ofproximal shaft member 360 about centerline through bore 192, pivoting ofproximal shaft member 360 about an axis perpendicular to centerlinethrough bore 192 and simultaneously perpendicular to centerline of bore195. In addition, when internal joint 190 (or 180) is in its free state,four additional motion degrees of freedom about axes A, B, D and E areprovided by virtue of the design of coronary stabilizer 30. Wheninternal joint 190 (or 180) is in its locked state the motion degrees offreedom offered by internal joint 190 (or 180) become locked. However,the four additional degrees of motion offered by the design of thecoronary stabilizer 30 may still be exploited through a surgeon inputapplied at either cradle 389, dial 331, dial 371 or any combinationthereof. A surgeon input applied at proximal control section 380 resultsin a linked corresponding movement of heart contact section 300 withinthe internal body cavity and downstream of anatomic barrier. As such,this provides an additional level of adjustment which may be exploitedto tend to optimize the presentation of coronary stabilizer 30 upon thebeating heart in addition to the “fine adjustment” and “coarseadjustment”. This additional level of adjustment also provides a meansfor readjusting the contact pressures exerted by the coronary stabilizerduring a surgical procedure, without having to disrupt the “fine” and“coarse adjustments”.

The design concepts described in reference to coronary stabilizer 30 mayalso be applied to a heart manipulator 20, especially if heartcontacting member 200 is a non-flowing static suction cup. As such, theheart contacting member 200 may be further deployed in space relative tothe distal end 226 of shaft member 220.

Referring to FIGS. 7, 11A and 11B, heart manipulator 20 and coronarystabilizer 30 are illustrated engaged with access cannula 10 and with abeating heart. Handle 240 and control section 380 extend beyond proximalopening 116 into the extracorporeal space ECS. Heart contacting member200 and heart-contacting section 300 extend into the pleural space PLSbeyond the diaphragm DG and downstream of open end 115. Heart contactingmember 200 and heart-contacting section 300 are engaged with targetinternal cardiac tissue, more specifically a portion of a beating heartsurface. FIG. 11A illustrates a beating heart oriented and positionedrelative to access cannula 10 by heart manipulator 20 so that coronarystabilizer 30 may access the posterior surface of the heart. FIG. 11Billustrates a beating heart oriented and positioned relative to accesscannula 10 by heart manipulator 20 so that coronary stabilizer 30 mayaccess the anterior surface of the heart.

FIGS. 17A-17D illustrate a variant to the first embodiment according tothe present invention. Coronary stabilizer 31 and heart manipulator 21are substantially fully enclosed within the at least one hollowpassageway 213 of access cannula 10, in an initial retracted state(FIGS. 17A, 17B). Hollow shaft 363 of coronary stabilizer 31 is engagedwith an internal joint (not shown) within hollow passageway 213, locatedupstream of seal member 211. Coronary stabilizer 31 is comprised of asubstantially fixed joint 364 between hollow shafts 363 and 366, and apivoting joint 365 between hollow shafts 366 and 367. Longitudinal axesof shafts 363 is substantially parallel to longitudinal axis of accesscannula 10. Shaft 366 is substantially perpendicular to shafts 363.

Contact member 310 is engaged with distal end of hollow shaft 367. Atleast three articulation cables (not shown) extend through each ofhollow shafts 367, 366, 363 and serve to position and orient contactmember 310 relative to shaft 367 in a similar manner to the firstembodiment. In addition, contact member 310 may also revolve around thelongitudinal axis of shaft 367 by virtue of a torsional cable alsodisposed along hollow shafts 367, 366, 363. A proximal control sectionsimilar to 380 of the first embodiment is also provided (not shown) totranfer the surgeon input to the heart contacting member 310.

Hollow shaft 209 of heart manipulator 21 is engaged with an internaljoint (not shown) within hollow passageway 213, located upstream of sealmember 211. Heart manipulator 21 is comprised of two hollow shafts 209,208 connected through a substantially rigid joint 210 in a substantiallyperpendicular orientation. The centerline of shaft 209 is substantiallyparallel with the longitudinal axis of access cannula 10. Heart contactmember 250 is comprised of an elastic conical sheath 206 which isrotatingly engaged with shaft 208 through rotatable pneumatic joint 207.Tissue-engaging perimeter 212 engages with the surface of the beatingheart in a similar fashion to the first embodiment. Said joint 207 isrotatable in order to provide torsion free displacements to a beatingheart which is engaged through sheath 206.

In the retracted state, hollow shaft 208 of heart manipulator 21 restsbetween the contact arms of contact member 310. Access cannula 10 ispreferably cylindrical and shafts 363, 209 are preferably diametricallyopposed relative to the centerline of access cannula 10. This tends tominimize the overall dimensions of access cannula 10 needed to fullyenclose coronary stabilizer 31 and heart manipulator 21 in the retractedstate within hollow passageway 213.

Heart manipulator 21 is deployed before coronary stabilizer 31. Heartmanipulator 21 is extended into the thoracic cavity sufficiently to beable to rotate freely about the centerline of shaft 209 withoutinterfering with contact arms of retracted coronary stabilizer 31. Heartmanipulator 21 may extend further into thoracic cavity until it iscapable of coming into contact with the target internal cardiac tissue,preferably the apex of the beating heart. The rotation of heart contactmember 250 about the centerline of shaft 209 is a “fine adjustment”motion degree of freedom enabled by the internal joint. Said internaljoint secures the position and orientation of heart manipulator 21relative to access cannula 10.

When access cannula 10 is secured in a desired position and orientationrelative to surgical arm 50 (coarse adjustment), and when the internaljoint engaged with shaft 209 of heart manipulator 21 is in its freestate, center CX of heart contact member 250 is free to assume anyposition along circumference CHC, for a given distance between point CXand center of said internal joint. As such, heart contact member 250orbits around the centerline of shaft 209. If sheath 206 is engaged withthe surface of a beating heart, then said sheath 206 also rotates aboutpoint CX as it orbits, by virtue of rotatable joint 207.

When access cannula 10 is re-oriented within channel clamp 510, therebyrotating about its centerline axis, circumference CHC orbits about thecenterline of access cannula 10 along a trajectory ORB. If the apex of abeating heart is engaged with sheath 206 during this re-orientation ofaccess cannula 10, then the apex will also orbit about the centerline ofaccess cannula 10 but will not rotate. By rotating access cannula 10 inthe manner just described, all surfaces of the heart are generallyaccessible by coronary stabilizer 31 which is independently deployedrelative to heart manipulator 21.

Referring to FIG. 17C, almost any point within the area ACHC may beengaged by sheath 206 through the combination of a rotation of heartcontact member 250 about the centerline of shaft 209 (fine adjustment)and a rotation of access cannula 10 about its centerline (coarseadjustment). Once engaged, this point may be subsequently positioned andoriented relative to access cannula 10 by a combination of coarse andfine adjustments

FIGS. 18A and 18B illustrate variants in heart contacting member 250.FIG. 18A illustrates a heart contacting member comprising a plurality ofsubstantially rigid finger-like protrusions 291. FIG. 18B illustrates aheart contacting member comprising a substantially hemi-cylindricalcradle 292 with perforations 294 to allow anchoring preferably to theapex tissue of a beating heart with an associated suture 293.

By way of a general overview, FIG. 20 illustrates a surgical apparatus 2according to a second embodiment of the present invention. The surgicalapparatus 2 is comprised of a surgical arm 50, an access cannula 10, aheart manipulator 20, a coronary stabilizer 30, and a variety ofendoscopic instruments 90. Endoscopic instruments 90 represent a varietyof surgical instruments well-suited to perform a surgical interventionon a beating heart while deployed through access cannula 10. At least aportion of each of the surgical instruments comprising endoscopicinstruments 90 is able to engage access cannula 10 through an internaljoint such as internal joint 180. Some of the surgical instrumentscomprising endoscopic instruments 90 may also be deployed through accesscannula 10 during a part of a surgical procedure without being engagedin said internal joint 180. Endoscopic instruments 90 are generallydeployed while heart manipulator 20 is engaged with a beating heart andwhile heart manipulator 20 is securing a desired position andorientation of said beating heart with the aim of facilitating thesurgical procedure performed by endoscopic instruments 90. In otherinstances, endoscopic instruments 90 may be deployed while both heartmanipulator 20 and coronary stabilizer 30 are engaged with a beatingheart. Endoscopic instruments 90 may be comprised of some conventionalendoscopic instruments capable of being engaged within said internaljoint 180.

FIG. 22A illustrates a surgical method of harvesting an internal mammaryartery IMA by using endoscopic instruments which are engaged with accesscannula 10. Endoscopic scissors 92 are used to section internal mammaryartery IMA from the internal wall of the thoracic cavity, whileendoscopic forceps 91 hold and suitably position the internal mammaryartery. Alternatively, endoscopic scissors 92 may be replaced by ascalpel, a cauterizing scalpel, an ultrasonic scalpel, or other likemeans.

FIG. 22B illustrates a surgical method for deploying a pericardialtraction suture 94 through the use of endoscopic instruments 90.Endoscopic forceps 91 pinch pericardium tissue PCT while endoscopicneedle holder 93 simultaneously pierces the pericardial tissue withneedle 941.

FIG. 22C illustrates a surgical method of securing a pericardialtraction load by engaging traction suture 942. A pericardial tractionsuture 942 is first engaged through an aperture 952 disposed on a member951, which extends distally away from the distal end of access cannula10 into the pleural space. Subsequently, said suture 942 is anchoredinto an anchoring port 955. Suture 942 is anchored by virtue of awedging action produced when plug 953 is inserted into aperture 954thereby trapping said suture 942.

FIG. 22D illustrates a surgical method of performing a proximalanastomosis of bypass graft BPG onto descending aorta DA. The methodillustrated comprises the use of a shape memory alloy stent to anchorbypass graft BPG to descending aorta DA. Bypass graft BPG may be engagedwith said stent extracorporeally prior to introducing said bypass graftinto the thoracic cavity. Alternatively, a side biting clamp can engagea portion of descending aorta DA thus isolating a part thereof and thebypass graft can be sutured onto the aorta after opening a suitablysized hole in the isolated portion of the aorta.

FIG. 22E illustrates a surgical method of performing an arteriotomyincision in a target artery. The target artery is occluded by engagingoccluding wires 303 in pedestals 310, and applying sufficient tension tooccluding wire such that snaring occurs. Endoscopic scissors 92 engagethe target artery to excise a portion thereof while beating heart BH islocally immobilized by engaging contact member 301 of coronarystabilizer 30 with the heart surface proximate to the target artery.Bulldog clamp 96 engages bypass graft BPG to occlude blood flow from thedescending aorta. Occluding wires 303 are engaged with the target arteryby using forceps 91. Forceps 91 and scissors 92 are deployed throughaccess cannula 10.

FIG. 22F illustrates a surgical method for performing of a distalanastomosis to a target coronary artery. Two forceps 91 engage andimmobilize bypass graft BPG while endoscopic needle holder 93 engagessuture 97 with bypass graft BPG. The proximal forceps 91 also functionto occlude the bypass graft and thus prevent bleeding through the patentgraft during surgery.

FIG. 22G illustrates a surgical method of performing dopplerultrasonography with an endoscopic ultrasonic doppler probe 971 engagedwith bypass graft BPG.

Referring to FIGS. 21A-21C, a hollow passageway 995 of an access cannula10 may be reserved for engagement with a cartridge 99. Cartridge 99 isconfigured with at least one hollow passageway 996 which extends from aproximal open end to a distal open end. At least one surgicalinstrument, such as a forcep 91, is preferably permanently engagedwithin an internal joint disposed within said hollow passageway 996. Aninternal joint such as 180 or 150 is preferable, although other internaljoints with fewer motion degrees of freedom may also be used. Hollowpassageway 996 may be provided with a seal member 70 (not shown) inorder to preserve the ambient conditions present within the internalbody cavity. A seal member 993 may also be provided within hollowpassageway 995 of access cannula 10 in order to preserve the ambientconditions present within the internal body cavity during changeover ofcartridges or when no cartridge is engaged with said hollow passageway995. Seal member 993 is displaced by cartridge 99 during installation ofsaid cartridge into passageway 995 as illustrated in FIG. 21C. As such,during the installation and removal of cartridge 99 there is always atleast one seal member, 993 or 70, acting to seal hollow passageway 995.When cartridge 99 is fully assembled into access cannula 10, distal end998 of representative surgical instrument 91 extends distally beyonddistal open end 115 of said access cannula 10, and proximal end 997extends proximally beyond proximal open end 116 of said access cannula10. A handle member in the nature of a flange 991 is also providedserving to limit the amount of insertion of said cartridge 99 into saidpassageway 995, and also serving to extract said cartridge 99 fromaccess cannula 10. Feature 992 on cartridge 99 and feature 997 on accesscannula 10 cooperate to provide a locking means between said cartridgeand said access cannula. For instance, a quarter turn fastener, adetented pin, a screw, a wire, or other like means may be used.Alternatively, locking may be provided by virtue of a snug fit betweencartridge 99 and access cannula 10.

A variety of cartridges may be assembled, wherein each cartridge iscomprised of a different surgical instrument. Each different cartridgeis intended for a different surgical procedure. Used in this manner,cartridges may facilitate or accelerate the substitution of a surgicalinstrument engaged in a hollow passageway of access cannula 10 by adifferent surgical instrument to be used in a subsequent surgicalintervention. A cartridge may also serve to bundle two or more differentsurgical instruments (or two or more similar surgical instruments),which are used in conjunction to perform a particular surgicalintervention. This allows a rapid changeover in surgical set-up from afirst surgical intervention to a subsequent different surgicalintervention. For instance, a cartridge bundling surgical instrumentsfor performing harvesting of an internal mammary artery may be rapidlydisengaged from access cannula 10 and replaced with a cartridge bundlingsurgical instruments for performing a distal anastomosis.

FIG. 12 illustrates a pericardium retraction device 69 may be engaged ina hollow passageway 120 of access cannula 10 through an internal joint180. In order to assist in the positioning and orienting of a beatingheart generally during posterior artery revascularization, a suture 67may be placed through the incised pericardium tissue 68. A pericardiumtraction force may be applied to said suture through said device 69.This helps to lift and orient the heart within the thoracic cavity. Theamount of protrusion of device 69 from the distal open end 115, alongwith the fine adjustment position and orientation of said device 69within internal joint 180 will determine a vector direction in which thepericardium retraction load is applied to pericardium tissue by virtueof engaged suture 67. Said pericardium retraction device may be usedsingly or may assist the heart manipulator 20 in setting the desiredposition and orientation of a beating heart.

In broad terms, the surgical procedure for the set-up and deployment ofthe surgical apparatus during a beating heart CABG surgery, and relatingto the present invention consists of:

-   1. Performing a single lung deflation, preferably on the left lung,    in order to augment the pleural space PLS available for subsequent    deployment of surgical apparatus within a closed chest;-   2. Inserting one or more visioning ports into the thoracic cavity    through intercostal port incisions (this step may be optional if    such ports will only be deployed through an access lumen in access    cannula 10);-   3. Performing an abdominal incision (AI) preferably in the upper    left quadrant of the patient;-   4. Inserting a laparoscopic cannula 499 into the abdominal incision    AI and directing it into the underlying extra-peritoneal space EPS,    generally in a direction towards the patient's head;-   5. Introducing CO2 gas through a hollow laparoscopic cannula 499 to    assist in the dissection of the extra-peritoneal space EPS and the    lateral displacement of viceral organs (VO) contained within the    peritoneum (PER);-   6. Creating a sagittal tunnel spanning from the site of the    abdominal incision AI to the patient's diaphragm DG, preferably in    the vicinity of the left leaflet of the diaphragm;-   7. Inserting a guide wire 400 through the center of laparoscopic    cannula 499 in order to pierce diaphragm and obtain access into the    thoracic cavity and more specifically the pleural space PLS;-   8. Retrieving from the patient's body laparoscopic cannula 499,    leaving behind guide wire 400 extending from the extracorporeal    space, through the abdominal incision, along the sagittal tunnel,    through the diaphragm, and into the pleural space;-   9. Channeling a hollow enlarging cannula 402 (with conical tip) over    guide wire 400 in order to reach the diaphragm and subsequently    pierce through said diaphragm, preferably with a Seldinger    technique, in order to obtain access into the pleural space;-   10. Inserting diaphragm tissue retractor 40 over enlarging cannula    402 in order to further pierce diaphragm;-   11. Retracting diaphragm tissue to obtain access into the thoracic    cavity and more specifically into the pleural space;-   12. Once the desired retracted opening in the diaphragm is obtained,    inserting access cannula 10 through the center of diaphragm    retractor 40 in a manner that the distal open end 115 of said    cannula extends at least partially within and communicates with the    pleural space;-   13. Retrieving the diaphragm retractor 40 from the patient's body    leaving in place access cannula 10 engaged with the retracted    diaphragm at location of weir 130;-   14. Deploying a visioning port into pleural space through an access    lumen in access cannula 10 (optional if only intercostal port access    will be used for vision system);-   15. Introducing CO2 gas into the closed chest thoracic cavity of the    patient either through an access lumen 125 in access cannula 10 or    through an intercostal port incision, thereby augmenting the    available pleural space through a displacement of the diaphragm    caused by a pressure load acting on the dome of the diaphragm;-   16. Alternatively, if CO2 is not introduced, applying a pulling load    to access cannula 10 which will also displace diaphragm by virtue of    its engagement with weir 130 thereby augmenting pleural space;-   17. Positioning and orienting access cannula 10 relative to the    patient's pleural space and target internal cardiac tissue contained    therein;-   18. Securing access cannula 10 in the desired position and    orientation through its engagement with surgical arm 50;-   19. Surgical harvesting of the internal mammary artery (IMA) if so    required for a bypass graft. Deploying a forcep and cauterizing    scalpel or a forcep and surgical scissor through the at least one    hollow passageway 120 of access cannula 10 (FIG. 22A);-   20. Incising the pericardium tissue of the beating heart, at least    in the vicinity of the target coronary artery, to expose the    myocardium prior to a distal anastomosis (for multi-vessel CABG    cases incising the pericadium along the long axis of the heart    preferably with an inverted T incision) (FIG. 22E);-   21. Engaging a portion of the surface of the beating heart,    preferably the apex, with a heart manipulator 20. (In single vessel    CABG cases the heart manipulator 20 may be engaged with the    pericardium tissue if the pericardiotomy incision was substantially    small);-   22. Deploying heart manipulator 20 in order to position and orient    the beating heart within the thoracic cavity in a desired position    and orientation for a surgical procedure;-   23. Rotating access cannula 10 with respect to its centerline in    order to select the optimum path for the deployment of coronary    stabilizer 30 through access cannula 10, given the specific patient    anatomy;-   24. If desired, engaging the pericardium tissue, preferably the    incised pericardium tissue, with a suture and applying a retraction    load through pericardium retraction device 69 to assist in the    positioning and orientation of the beating heart;-   25. Deploying coronary stabilizer 30 through access cannula 10 while    engaged in internal joint 180. Position and orient the heart contact    member 301 through the numerous motion degrees of freedom offered in    such a manner as to align the arterial window with the target    coronary artery and the heart contact plane substantially tangent to    the surface of the heart proximate to the target artery.-   26. Compressing the heart surface gradually until pulsating effect    of beating heart is substantially suppressed by virtue of the    imposed immobilization load.-   27. Securing the position and orientation of the coronary stabilizer    through internal clamp 180, securing bolt 385, dial 371, and dial    331;-   28. Entering a bypass vascular conduit into the pleural space either    through a hollow passageway 120 or a designated access lumen 125 of    access cannula 10. The vascular conduit may be kept engaged with a    forceps 91 that is secured in a desired position and orientation    relative the beating heart thereby facilitating the distal    anastomosis.-   29. Occluding the target coronary artery, at a location upstream and    downstream of the grafting site, with two occluding wires 303 that    are manipulated and placed into engagement with both the beating    heart and pedestals 310 of the coronary stabilizer 30, by two    forceps 91 deployed through access cannula 10;-   30. Performing an arteriotomy incision through the arterial window    304 of the coronary stabilizer 30 with a surgical scissors 92    deployed through access cannula 10;-   31. Performing a distal anastomosis through the arterial window 304    of coronary stabilizer 30 with two forceps 91 and one needle holder    93 deployed through access cannula 10;-   32. Verifying graft patency of newly grafted conduit with an    endoscopic ultrasonic Doppler 97 deployed through access cannula 10;-   33. Performing a proximal anastomosis on the aorta, preferably the    descending aorta, with an endoscopic surgical instrument capable of    rapidly connecting a shape memory alloy stent to which a vascular    conduit is affixed to said descending aorta;-   34. Alternatively, performing a proximal anastomosis on the aorta by    deploying an endoscopic side biting clamp, an endoscopic hole punch,    an endoscopic forceps 91, and one endoscopic needle holder 93    through access cannula 10;-   35. Verifying graft patency of newly grafted conduit with an    endoscopic ultrasonic Doppler 97 deployed through access cannula 10;-   36. Once the distal and proximal anastomosis is completed,    disengaging coronary stabilizer 30 from the beating heart surface    and retract from said surface;-   37. In multi-vessel CABG surgeries, repeating procedure (steps    22-36) for other target coronary arteries arteries;-   38. Once all diseased arteries have been revascularized, retrieving    access cannula 10 from the patient's body;-   39. Re-inflating deflated lung, and proceed to closing all surgical    incisions through standard medical practice.

A variety of different coronary artery grafts may be performed with thesurgical apparatus according to the present invention. These include: avenous conduit grafted proximally to the descending aorta and distallyto a target coronary artery, a harvested internal mammary artery grafteddistally to a target coronary artery, a venous conduit graftedproximally to the substantially non-harvested internal mammary arteryand distally to a target coronary artery; a radial artery conduitgrafted proximally to the descending aorta and distally to a targetcoronary artery;

In the preferred embodiments according to the present invention, accessto the thoracic cavity was achieved by piercing at least a portion ofthe diaphragm. Alternatively, the concepts and principles of the presentinvention may also be applied to a thoraco-phrenic dissociation surgicalapproach, whereby access to the thoracic cavity is achieved through atunnel or passage created between the diaphragm and the patient'sribcage without piercing or penetrating the diaphragm.

In the preferred embodiments according to the present invention, accessto the diaphragm and subsequently the thoracic cavity was achieved viathe extraperitoneal space. Alternatively, the concepts and principles ofthe present invention may also be applied to an intraperitoneal surgicalapproach, in which at least a portion of the patient's peritonealmembrane is pierced or penetrated prior to attaining the thoracic cavitybeyond the diaphragm.

Those skilled in the art will appreciate that the anatomic routingselected to attain the thoracic cavity according to the presentinvention may vary without departing from the spirit of the invention.Also, the thoracic cavity may be attained simultaneously though thedeployment of one or more access cannulae 10 according to the presentinvention. For instance, one access cannula may be deployed to accessthe left pleural space, and one may be deployed to access the rightpleural space.

Some of the features and concepts of the surgical apparatus according tothe present invention may also be used in cardiac surgery performedthrough an open chest approach, whereby the patient's thoracic structureis not left anatomically intact during the said cardiac procedure. Forinstance, open chest cardiac surgery performed through a sternotomyincision where the patient's sternum is incised the ribcage subsequentlyretracted, open chest cardiac surgery performed though an intercostalthoracotomy where two adjacent ribs are laterally spread apart, openchest cardiac surgery through an intercostal thoracotomy including apartial extraction of a portion of a rib, or other open chest cardiacsurgeries performed through other like surgical incisions in order toaccess internal cardiac tissue. In these open chest cardiac surgeries,the patient's thoracic structure constitutes the anatomic barrieraccording to the present invention.

In the same spirit, some of the features and concepts of the surgicalapparatus according to the present invention may also be used in cardiacsurgery performed through an intercostal access port whereby thepatient's thoracic structure is left anatomically intact (closed chest)during the said cardiac procedure. Here again the patient's thoracicstructure constitutes the anatomic barrier according to the presentinvention.

A number of preferred embodiments have been described in detail and anumber of alternatives have also been described. As changes in, oradditions to, the above described embodiments may be made withoutdeparting from the nature, spirit or scope of the invention, theinvention is not limited by or to those details, but only by theappended claims.

1. A method for performing an intervention on a target anatomicstructure of a patient body using an implement, said target anatomicstructure including a biological tissue, said body defining an abdominalcavity and a thoracic cavity separated by a diaphragm, said thoraciccavity being at least in part protected by a ribcage and containing atleast a portion of said target anatomic structure, said diaphragm beingat least in part attached to said ribcage, said body also including anon-target anatomic structure, said method comprising the steps of:altering the configuration of said diaphragm to create a passagewayleading into said thoracic cavity; introducing said implement at leastpartially into said thoracic cavity through said passageway in animplement operational configuration; and using said implement while theimplement extends through said passageway to perform said interventionon said target anatomic structure, said intervention includingperforming a coronary artery bypass graft.
 2. A method as recited inclaim 1 wherein the step of altering the configuration of said diaphragmincludes displacing said diaphragm.
 3. A method as recited in claim 1wherein the step of altering the configuration of said diaphragmincludes dissociating at least partially said diaphragm from saidribcage.
 4. A method as recited in claim 1 wherein said implement ispositioned in said implement operational configuration through athoraco-phrenic dissociation by inserting said implement between saidribcage and said diaphragm.
 5. A method as recited in claim 1 whereinthe step of altering the configuration of said diaphragm includes thestep of traversing said diaphragm.
 6. A method as recited in claim 1wherein said implement is positioned in said implement operationalconfiguration by inserting said implement through said diaphragm.
 7. Amethod as recited in claim 1 further comprising the step of insertingsaid implement at least partially into said abdominal cavity prior tointroducing said implement at least partially into said thoracic cavitythrough said diaphragm.
 8. A method as recited in claim 1 wherein saidintervention is performed at least partially while said implementextends at least partially into both said abdominal and thoraciccavities and through said diaphragm.
 9. A method as recited in claim 1wherein said implement is positioned so as to extend at least partiallyinto the extra-peritoneal space of said abdominal cavity withoutpenetrating into the peritoneal space of the abdominal cavity.
 10. Amethod as recited in claim 1 wherein said intervention is performed atleast partially while said implement extends from the exterior of saidpatient body, into said abdominal cavity, through said diaphragm andinto said thoracic cavity.
 11. A method as recited in claim 1 whereinsaid intervention includes the step of traversing across an externalsurface of said biological tissue.
 12. A method as recited in claim 1wherein said intervention includes the step of severing at least aportion of said biological tissue.
 13. A method as recited in claim 1wherein said intervention includes the step of puncturing at least aportion of said biological tissue.
 14. A method as recited in claim 1wherein said intervention includes the step of retracting at least aportion of said biological tissue.
 15. A method as recited in claim 1wherein said coronary artery bypass graft is performed on a beatingheart.
 16. A method as recited in claim 1 further including the stepsof: selecting a separating component, said separating component having acomponent peripheral wall at least partially encompassing a componentchannel, said separating component being usable to at least partiallyseparate said component channel from said non-target anatomic structure;introducing said separating component at least partially into saidthoracic cavity through said passageway in a separating componentoperational configuration; and using said separating component forpositioning said implement in said implement operational configuration.17. A method as recited in claim 16 further comprising the step of atleast temporarily coupling said separating component to said diaphragm.18. A method as recited in claim 16 further comprising the step of atleast temporarily coupling said separating component in a predeterminedspatial relationship relative to said thoracic cavity.
 19. A method asrecited in claim 16 further comprising the step of at least temporarilycoupling said implement to said separating component.
 20. A method asrecited in claim 16 wherein said separating component is inserted in anaccess aperture formed in said diaphragm, said access aperture beingformed by using a piercing instrument to pierce a lead aperture in saiddiaphragm.
 21. A method as recited in claim 16 wherein said separatingcomponent extends in the extra-peritoneal space of said abdominalcavity, without penetrating into the peritoneal space of the abdominalcavity.
 22. A method as recited in claim 1 wherein said intervention isselected from the group consisting of stabilizing said target anatomicstructure within said thoracic cavity and positioning said targetanatomic structure within said thoracic cavity.
 23. A method as recitedin claim 1 wherein said intervention includes suctioning at least aportion of said target anatomic structure.
 24. A method as recited inclaim 1 wherein said intervention includes grasping at least a portionof said target anatomic structure.
 25. A method as recited in claim 1wherein said intervention includes abuttingly contacting at least aportion of said target anatomic structure.
 26. A method as recited inclaim 1 wherein said intervention includes harvesting of a vascularconduit for use in said revascularization procedure.
 27. A method asrecited in claim 1 wherein said intervention includes assessing bloodflow through a vascular conduit of said target anatomic structure.
 28. Amethod as recited in claim 1 wherein said intervention includescontrolling blood flow through a vascular conduit of said targetanatomic structure.
 29. A method for performing an intervention on atarget anatomic structure of a patient body using a first and a secondimplement, said target anatomic structure including a biological tissue,said body defining an abdominal cavity and a thoracic cavity separatedby a diaphragm, said thoracic cavity being at least in part protected bya ribcage and containing at least a portion of said target anatomicstructure, said diaphragm being at least in part attached to saidribcage, said body also including a non-target anatomic structure, saidmethod comprising the steps of: altering the configuration of saiddiaphragm to create a passageway leading into said thoracic cavity;introducing both said first and second implements at least partiallyinto said thoracic cavity through said passageway respectively in afirst implement operational configuration and in a second implementoperational configuration; cooperatively using both said first andsecond implements while the first and second implements are respectivelyin said first and second implement operational configurations to performsaid intervention on said target anatomic structure; selecting aseparating component, said separating component having a componentperipheral wall at least partially encompassing a component channel,said separating component being usable to at least partially separatesaid component channel from said non-target anatomic structure;introducing said separating component at least partially into saidthoracic cavity through said passageway in a separating componentoperational configuration; using said separating component forpositioning said first and second implements respectively in said firstand second implement operational configurations; and wherein one of saidfirst or second implements is a beating heart stabilizer, said methodfurther comprising the step of exerting a stabilizing force on a beatingheart with said beating heart stabilizer.
 30. A method as recited inclaim 29 further comprising the steps of: movably coupling said beatingheart stabilizer to said separating component so as to allow a relativemovement therebetween; and locking said beating heart stabilizer andsaid separating component in a predetermined spatial relationshiprelative to each other to maintain said stabilizing force on saidbeating heart, at least for part of said intervention.
 31. A method asrecited in claim 29 wherein one of said first or second implements is aheart manipulator, said method further comprising the step ofpositioning a heart with said heart manipulator within said thoraciccavity.